Chapter 3. Cellular Concept

Size: px
Start display at page:

Download "Chapter 3. Cellular Concept"

Transcription

1 Chapter 3 Cellular Concept

2 Contents 3.1 Introduction 3.2 Frequency Reuse 3.3 Channel Assignment Strategies 3.4 Handoff Strategies 3.5 Interference and System Capacity 3.6 Trunking and Grade of Service 3.7 Improving Coverage and Capacity in Cellular Systems

3 3.1 Introduction The cellular concept was a major breakthrough in solving the problem of spectral congestion and user capacity. It offered very high capacity in a limited spectrum allocation without any major technological changes. The cellular concept is a system-level idea.

4 3.2 Frequency Reuse 3.1 Introduction 3.2 Frequency Reuse 3.3 Channel Assignment Strategies 3.4 Handoff Strategies 3.5 Interference and System Capacity 3.6 Trunking and Grade of Service 3.7 Improving Coverage and Capacity in Cellular Systems

5 Cellular Structure: Fig

6 Basic Properties of Hexagon d = 3R R Area = 6* 3R 2 * R 2 = R 2

7 Minimal distance of the same frequency cells (1d,2d) (2d,2d) (2d,1d) 120 (0,0) Center coordinates:(0,0); Target :( id, jd) D id jd i d j d ijd ((, ),(0,0)) = + 2 cos(120 ) = d i j ij

8 Frequency reuse concept Frequency reuse concept S: Total of duplex channels in a cluster k: A group of channels for one cell N: Number of cells to use S channels S=kN (3.1) Cluster size: N ( 区群大小 ) N: The number of cells to use the complete available frequency. Total number of duplex channels: C C = MkN = MS M: reuse times of cluster within the system.

9 Calculational equation of N: N = i 2 + ij + j Example: i=2, j= N=

10 D = 7d

11 Important Formula D N D D R = d = i = d i + j + ij 2 + j + ij N = R 3N 3N The capacity of a cellular system is directly proportional to the number of times a cluster is replicated in a fixed service area.(the N cells which collectively use the complete set of available frequencies is called a cluster). The frequency reuse factor of the cellular system is given by 1/N. = 2 2 2

12 Example 3.1 Total bandwidth= 33MHz, Channel BW=25kHz 2 simplex channels =50kHz/duplex channel Total available channels =33000/50= 660, The total number of cells within service area = 49 1) N = 4, four cells 33MHz bandwidth, total number of channel available per cell =660/4= 165, duplex channel C=(49/4) 660=8084 2) N = 7,seven cells 33MHz bandwidth, total number of channel available per cell = 660/7=95, duplex channel C=(49/7) 660=4620 3) N = 12, twelve cells 33MHz bandwidth, total number of channel available per cell = 660/12=55, duplex channel C=(49/12) 660=2694

13 3.3 Channel Assignment Strategies 3.1 Introduction 3.2 Frequency Reuse 3.3 Channel Assignment Strategies 3.4 Handoff Strategies 3.5 Interference and System Capacity 3.6 Trunking and Grade of Service 3.7 Improving Coverage and Capacity in Cellular Systems

14 Principle: efficient utilization of the radio spectrum Frequency reuse scheme is consistent with the objectives of increasing capacity and minimizing interference is required. Assignment strategies: fixed and dynamic. Fixed assignment: The choice of channel assignment strategy impacts the performance of the system, particularly as to how calls are managed when a mobile used is handed off from one cell to another. In a fixed channel assignment strategy (borrowing strategy), each cell is allocated a predetermined set of voice channels.

15 Dynamic assignment: In a dynamic channel assignment strategy, instead, each time a call request is made, the serving BS requests a channel from the MSC. The switch then allocates a channel to the requested cell. following an algorithm that takes into account the likelihood of future blocking within the cell, the frequency of use of the candidate channel, the reuse distance of the channel, and other cost functions.

16 Dynamic assignment: Dynamic channel assignment reduce the likelihood of blocking, which increase the trunking capacity of the system. Dynamic channel assignment strategies require the MSC to collect real-time data on channel occupancy, traffic distribution, and RSSI (Radio Signal Strength Indications) of all channel on a continuous basis.

17 3.4 Handoff Strategies 3.1 Introduction 3.2 Frequency Reuse 3.3 Channel Assignment Strategies 3.4 Handoff Strategies 3.5 Interference and System Capacity 3.6 Trunking and Grade of Service 3.7 Improving Coverage and Capacity in Cellular Systems

18 Handoff: A mobile moves into a different cell while a conversation is in progress. The MSC transfers the call to a new channel belonging to new BS. Important task of any cellular systems Handoff threshold of signal level: - 90dbm~-100dbm (-110dbm~-120dbm)

19 Handoff: Dwell time ( 驻留时间 ) A call may be maintained within cell, without handoff Handoff strategy In 1G, handoff is made by BS, supervised by MSC. In 2G, handoff division is mobile assisted (MAHO) Intersystem handoff Prioritizing handoff ( 优先切换 )

20 Handoff algorithm s parameters: signal level handoff threshold handoff time dwell time As Fig 3.3

21 不正确的切换情况 接收到的信号强度 A 点信号强度切换门限维持通话的最小可接收信号 B 点信号强度 ( 通话中断 ) 正确的切换情况 接收到的信号强度 时间 B 点信号强度切换时的信号强度 ( 通话成功转移到 BS2) 时间 基站 1 A B 基站 2

22 In 1G analog cellular systems, signal strength measurements are made by the BSs and supervised by the MSC. The typical time is to make a handoff = 10s, The handoff threshold is at 6-12dB. In today s 2G systems, in mobile assisted handoff (MAHO), Typically time required only = 1-2s, Handoff threshold is at 0-6dB. Intersystem handoff: Handoff occurs among different MSC.

23 3.4.1 Prioritizing Handoffs One method for giving priority to handoffs is called the guard channel concept ( 信道守候 ), whereby a fraction of the total available channels in a cell is reserved exclusively for handoff requests from ongoing calls which may be handed off into the cell. Queuing of handoff requests ( 排队请求 ) is another method to decrease the probability of forced termination of a call due to lack of available channels.

24 3.4.2 Practical Handoff Considerations High speed vehicles and Walking people, fig 3.4 Cell dragging ( 小区拖尾 ) Handoff decision bases on a wide range of metrics other than signal strength. 为高速通信设置的 伞状 宏小区 为低速通信设置的微小区

25 3.5 Interference and System Capacity 3.1 Introduction 3.2 Frequency Reuse 3.3 Channel Assignment Strategies 3.4 Handoff Strategies 3.5 Interference and System Capacity 3.6 Trunking and Grade of Service 3.7 Improving Coverage and Capacity in Cellular Systems

26 Interference is the major limiting factor in the performance of cellular radio systems. Interference Sources: another mobile in the same cell call in progress in a neighboring cell other BS operating in the same frequency or any noncellular system The two major type of cellular interference: co-channel interference adjacent channel interference.

27 3.5.1 Co-channel interference and System Capacity Co-channel cells: The cells that use the same set of frequencies in a given coverage area. Co-channel interference: The interference between signals from co-channel cells. To reduce co-channel interference Co-channel cells must be physically separated by a minimum distance to provide sufficient isolation due to propagation.

28 The co-channel interference is a function of the radius of the cell (R) and the distance (D) between centers of the nearest cochannel cells. co-channel reuse ratio Q=D/R=(3N) 1/2 A small value of Q provides larger capacity since the cluster size N is small, whereas a large value of Q improves the transmission quality, due to smaller level of co-channel interference.

29

30 Co-channel reuse rate : Q ( 同道复用比 ) Q = D/R = (3N) 1/2 D: distance to the center of nearest co-channel cell R: radius of the cell. N: cluster size

31 Signal to Interference Ratio (S/I) for cochannel interference cell I i is the co-channel interference from the ith interfering cell. S is the desired signal power from the desired base station, as following. d S P d = 0 0 n S I S = I i i P 0 is the power received from close-in reference point. d 0 is small distance from the antenna of close-in reference point.

32 Assume user is at the edge of the cell, Signal to Interference Ratio for cochannel interference cell is S I = i P 0 P i R d 0 D d i 0 n n D i is the distance between the center of the ith interfering cell and the user. n is the path loss exponent.

33 When the transmit power of each base station is equal and the path loss exponent is the same, S/I is = = = ) ( i i n i n i n i i n D R d D P d R P I S

34 Considering only the first layer of interfering cells and this distance is equal to the distance D between cell centers. S/I is S ( D / R) n ( 3N ) n = = I i 0 i 0

35 Consider only the 1 st layer of interfering cells (i 0 =6, as following Fig (N=7)) S I = D R n / 6 1 st layer of cells In db: R D D 10n log R 7.8

36 Example: For the US AMPS, use FM and 30kHz channels, voice quality is provided when SIR>=18dB. To meet this requirement, N should be at least Assuming n=4, thus a minimum N=7 is required to meet an SIR requirement of 18dB (Actually =17.8dB). N=7, Q=4.6, the worst case SIR=48.56(17dB).

37 Other consideration 18 If S/I requirement is 18dB, what is the recommended cluster size? (Assume n =4) log N = 40log D R i = D = 3N R N 6.52 i = 2 + D R 25.8/ j ij = = 2, j = 1or i = 1, j = 2 N = D R D N D 7 = = = = D 10n log R 4.42 d i d 2 i + 2 j N + 2 = j + 2 ij R ij 3N

38 Using an exact cell geometry layout, it can be shown for a seven-cell cluster using the same frequency, with the mobile unit at the cell boundary. A A D+R A SIR = 4 R 2( D R) + 2( D+ R) + 2D A D D-R R A D-R D D+R A = 1 2( Q 1) + 2( D+ 1) + 2Q A

39 Example 3.2 SIR=15dB is required for satisfactory forward channel performance of a cellular system, N=?,Q=? Assume that there are six co-channel cells in the first tire, and all of them are at the same distance for the mobile. (a) n=4, consider a seven-cell reuse pattern, D/R=(3N) 1/2 =4.583, SIR=(1/6) (4.583) 4 =75.3=18.66dB (b) n=3, consider a seven-cell reuse pattern, SIR=(1/6) (4.583) 3 =16.04=12.05dB. Since this is less than the minimum required SIR, we need to use a larger N. The next possible value of N=12(I=2, j=2), D/R=6, SIR=(1/6) (6) 3 =36=15.56dB>15dB.

40 f 3 f 2 f 1 f 1 f 3 f 2 f 3 f 1 f 2 f 1 f 3 f 2 f 3 f 2 f 1 f 1 f 3 f 2 f 3 f 1 f 2 f 1 f 3 f 2 f 3 f 2 f 1 f 1 f 3 f 2 f 3 f 1 f 2 f 1 f 3 f 2 N=3

41 f 3 f 4 f 3 f 4 f 3 f 4 f 3 f 2 f 1 f 2 f 1 f 2 f 1 f 4 f 3 f 4 f 3 f 4 f 3 f 4 f 1 f 2 f 1 f 2 f 1 f 2 f 3 f 4 f 3 f 4 f 3 f 4 f 3 f 2 f 1 f 2 f 1 f 2 f 1 N=4

42 f 7 f 8 f 9 f 7 f 8 f 9 f 7 f 8 f 9 f 4 f 5 f 1 f 6 f 2 f 3 f 4 f 1 f 5 f 6 f 2 f 3 f 4 f 1 f 5 f 6 f 2 f 7 f 8 f 9 f 7 f 8 f 9 f 7 f 8 f 9 f 7 f 4 f 5 f 1 f 6 f 2 f 3 f 4 f 1 f 5 f 6 f 2 f 3 f 4 f 1 f 5 f 6 f 2 f 3 f 7 f 8 f 9 f 7 f 8 f 9 f 7 f 8 f 9 f 4 f 5 f 1 f 6 f 2 f 3 f 4 f 1 f 5 f 6 f 2 f 3 f 4 f 1 f 5 f 6 f 2 N=9

43 3.5.2 Channel Planning for Wireless Systems Judiciously assigning the appropriate radio channels to each base station is an important process that is much more difficult in practice than in theory. Generally, the available mobile radio spectrum is divided into channels (about 5% control channel), which are part of an air interface standard that is used throughout a country or continent. One of the key features of CDMA systems is that N=1, and frequency planning is not nearly as difficult as for TDMA or first generation cellular systems. Breathing cell : a dynamic, time varying coverage region which varies depending on the instantaneous number of users.

44 3.5.3 Adjacent Channel Interference Interference resulting from signals which are adjacent in frequency to the desired signal is called adjacent channel interference(aci). Adjacent channel interference can be minimized through careful filtering and channel assignments. If N is small, the separation between adjacent channels at the BS may not be sufficient to keep the ACI level within tolerable limits. In practice, BS receivers are preceded by a high Q cavity filter in order to reject ACI.

45 Example: If a close-in mobile is 20 times as close to the BS as another mobile and has energy spill out of its passband, the signal to interference ratio is SIR=(20) -n, n=4, SIR=-52dB If the IF filter has a slope of 20dB/octave, then the ACI must be displaced by at least 6 times the passband bandwidth from the center of the receiver frequency passband to achieve 52dB attenuation.

46 3.5.4 Power Control for Reducing Interference In practical cellular systems, the power levels transmitted by every subscriber unit are under constant control by the serving base station, and are done to ensure them to maintain a good quality link.

47 3.6 Trunking and Grade of Service 3.1 Introduction 3.2 Frequency Reuse 3.3 Channel Assignment Strategies 3.4 Handoff Strategies 3.5 Interference and System Capacity 3.6 Trunking and Grade of Service 3.7 Improving Coverage and Capacity in Cellular Systems

48 Cellular radio systems rely on trunking to accommodate a large number of users in a limited radio spectrum. The concept of trunking allows a large number of users to share the relatively small number of channels in a cell by providing access to each user, from a pool of available channels. Trunking exploits the statistical behavior of users so that a fixed number of channels or circuits may accommodate a large, random user community.

49 It should be clear that the allocation of channels in a trunked radio system has a major impact on overall system capacity. The fundamentals of trunking theory were developed by Erlang. The Grade of Service (GOS) is a measure of the ability of a user access a truncked system during the busies hour. GOS gives the likelihood that a call is blocked, or the likelihood of a call experiencing a delay greater than a queuing time.

50 Table3.3 Definitions of common terms used in trunking theory Set-up time: 给请求的用户分配一个中继无线信道所需的时间 Blocked call: 拥塞无法在请求时间完成的呼叫, 叫损失呼叫 Holding time: 通话的平均保持时间, 表示为 H( 以秒为单位 ) Traffic intensity: 表征信道时间利用率, 为信道的平均占用率以 Erlang 为单位 是一个无量纲的值, 可用来表征单个或多个信道的利用率 表示为 A Load: 整个系统的话务量强度, 以 Erlang 为单位 GOS: 表征拥塞的量, 定义为呼叫阻塞概率 ( 表示为 B, 单位为 Erlang), 或是延迟时间大于某一特定时间的概率 ( 表示为 C, 单位为 Erlang) Request rate: 单位时间内平均的呼叫请求次数 表示为 λ/ 秒

51 Simple Capacity Analysis Based on Blocking Probability Each user generates a traffic intensity of A u Erlangs given by A u = λh H is the average duration of a call λ is the average number of call requests per unit time for each user The total offered traffic intensity: A = UA u U is number of containing user in a system The traffic intensity per channel: Ac = UAu / C C is the total number of duplex channels

52 Concept of Blocked Traffic Define carried load as the portion of offered load that successfully obtains channel resources Since there is no queueing or buffering space, the remaining traffic will be blocked Offered load = Carried load + Blocked traffic Offered load Carried load Blocked traffic

53 Erlang B Formula A formula to predict blocking probability Assume: C is number of channels (servers), Poisson arrival with rate is λ, mean holding time is 1/µ, and X(t) is a Markov process if holding time is exponentially distributed to represent the number of occupied channels at time t. For there is no queueing or buffering space, the remaining traffic will be blocked The blocking probability P ( t) = Prob( X ( t) = i) i

54 Erlang B Formula (cont.) P ( t) = Prob( X ( t) = i) i dpi ( t) dt lim = t 0 P i ( t + t) t P i ( t) For the equilibrium state, that is, dp i /dt=0 for all i: C A P [blocking]! r = C = GOS P80, figure3.6 C k A k! k = 0

55 Trunking System Capacity Count (1) The Erlang B formula is derived in Appendix A.1 A P [blocking] = C! = GOS P80, figure3.6 r C A k k! k = 0 C C is the number of trunked channels A is the total offered traffic

56 Erlang B chart describes the relation between system capacity, offered load, and blocking probability

57 Trunking System Capacity Count (2) The Erlang C formula is given in Appendix A.2 (a queue is provided to hold calls which are blocked). For there is buffering space, the remaining traffic will be queued. P [ delay>0] = r C + C!1 C ( A ) C = 0 k P [ delay>t ] = P [ delay>0]exp( ( C A) t / H ) p81, figure3.7 r A r A C A H The average delay for all calls in a queued system is D= 延迟 Pr [ >0 ] C k k! A

58

59 Example 3.4 How many users can be supported for 0.5% blocking probability for the following number of trunked channels in a blocked calls cleared system?(assume each user generates 0.1Erlangs of traffic) (a) C=1, A u =0.1, GOS= From fig. 3.6, A=0.005, U=A/A u =0.005/0.1=0.05users, actually, U=1 user. (b) C=5, A u =0.1, GOS= From fig. 3.6, A=1.13, U=A/A u =1.13/0.1=11 users. (c) C=10, A u =0.1, GOS= From fig. 3.6, A=3.96, U=A/A u =3.96/0.1=39 users. (d) C=20, A u =0.1, GOS= From fig. 3.6, A=11.1, U=A/A u =11.13/0.1=110 users. (e) C=100, A u =0.1, GOS= From fig. 3.6, A=80.9, U=A/A u =80.9/0.1=809 users.

60 Example 3.5 An urban has two million residents. Three mobile networks provide cellular service. System A has 394 cells, each with 19 channel, system B has 98 cells, each with 57 channels, and system C has 49 cells, each with 100 channels. Find the number of users that can be supported at 2% blocking if each user average two calls per hour at an average call duration of 3 minutes. Assuming that all three systems are operated at maximum capacity, compute the percentage market penetration.

61 Solution: (a) GOS=0.02, C=19, A u =λh=2 (3/60)=0.1 Erlangs. From fig. 3.6, A=12, U=A/A u =12/0.1=120 users. Since there are 394 cells in system A, the total number of users that can be supported = = (b) GOS=0.02, C=57, A u =λh=2 (3/60)=0.1 Erlangs. From fig. 3.6, A=45, U=A/A u =45/0.1=450 users. Since there are 98 cells in system B, the total number of users that can be supported =450 98= (c) GOS=0.02, C=100, A u =λh=2 (3/60)=0.1 Erlangs. From fig. 3.6, A=88, U=A/A u =88/0.1=880 users. Since there are 49 cells in system C, the total number of users that can be supported =880 49=43120.

62 Example 3.6 A certain city has an area of 1,300 square miles and is covered by a cellular system using a seven cell reuse pattern. Each cell has a radius of four miles and the city is allocated 40 MHZ of spectrum with a full duplex channel bandwidth of 60 khz. Assume a GOS of 2% for an Erlang B system is specified. If the offered traffic per user is 0.03 Erlangs, compute (a) the number of cells in the service area, (b) the number of channels per cell, (c) traffic intensity of each cell, (d) the maximum carried traffic, (e) the total number of users that can be served for 2% GOS, (f) the number of mobiles per unique channel (where it is understood that channels are reused), (g) the theoretical maximum number of users that could be served at one time by the system.

63 Solution: (a) Given: Total coverage area=1300 miles, and cell radius =4 miles The area of a cell (hexagon)can be shown to be R 2, thus each cell covers (4) 2 =41.57 sq.mi. Hence, the total number of cells are N c =1300/41.57=31 cells. (b) The total number of channels per cell (C) = allocated spectrum/(channel width frequency reuse factor) = 40,000,000/(60,000*7)=95 channels/cell

64 (c) Give : C=95, and GOS=0.02 From the Erlang B chart, we have traffic intensity per cell A=84 Erlangs/cell (d) Maximum carried traffic = number of cells traffic intensity per cell = =2604 Erlangs. (e) Given traffic per user = 0.03 Erlangs Total number of users = Total traffic/traffic per user = 2604/0.03 =86,800 users. (f) Number of mobiles per channel =number of users / number of channels = 86,800/666=130 mobiles /channel.

65 (g) The theoretical maximum number of served mobiles is the number of available channels in the system (all channels occupied) = C N c = 95 31= 2945 users, which is =2945/86800=3.4% of the customer base.

66 Example 3.7 A hexagonal cell within a four-cell system has a radius of 1.389km. A total of 60 channels are used. Compute the following for an Erlang C system that has a 5% probability of a delayed call: (Assume the load per user is Erlangs and λ=1 call/hour) (a) how many users/km 2 will this system support? (b) what is the probability that a delayed call will have to wait for more than 10s? (c) what is the probability that a call will be delayed for more than 10s?

67 Solution: (a) R=1.387km, number of cells per cluster=4, C=60/4=15, area covered per cell=2.598 (1.378)^2 =5 sq km, A u =0.029, GOS=0.05. From fig. 3.7, A=9, U=A/A u =9/0.029= 310 users/5 sq km=62. (b) λ=1, holding time H= A u / λ=0.029 hour=104.4s, Pr[delay>t delay]=exp(-(c-a)t/h) =exp(-(15-9)10/104.4) =56.29% (c) Pr[delay>0]=5%=0.05 Pr[delay>t]= =2.81%.

68 3.7 Improving Coverage and Capacity in Cellular Systems 3.1 Introduction 3.2 Frequency Reuse 3.3 Channel Assignment Strategies 3.4 Handoff Strategies 3.5 Interference and System Capacity 3.6 Trunking and Grade of Service 3.7 Improving Coverage and Capacity in Cellular Systems

69 3.7.1 Cell Splitting ( D/R is constant, R is decreased ) Cell Splitting is the process of subdividing a congested cell into smaller cells, each with its own base station and a corresponding reduction in antenna height and transmitter power. It increases the capacity of a cellular system since it increases the number of times that channels are reused. Theoretically, if all cells were microcells having half the radius of the original cell, the capacity increase would approach four.

70 C D E G D C F D E A F B E C B G C G D E B G F

71 If the new cells are smaller in size with radius half that of the original cells, n=4, P t1 and P t2 are the transmit powers of the larger and smaller cell base stations, then P = t2 Pt 1 16 The powers at old cell boundary and new cell boundary are P [ at r old cell boundary ] Pt 1 R n P r[ at new cell boundary] Pt 2 ( R / 2) n

72 Example of Cell Splitting Arrangement II Example of Cell Splitting Arrangement III

73 Example 3.8 Consider Figure 3.9. Assume each base station uses 60 channels, regardless of cell size. If each original cell has a radius of 1 km and each microcell has a radius of 0.5 km, find the number of channels contained in a 3 km by 3 km square centered around A under the following conditions: (a) without the use of microcells; (b) when the lettered microcells as shown in Figure 3.9 are used; and (c) if all the original base stations are replaced by microcells. Assume cells on the edge of the square to be contained within the square.

74 C D E G D C F D E A F B E C B G C G D E B G F

75 Solution (a) without the use of microcells: A cell radius of 1 km implies that the sides of the larger hexagons are also 1 km in length. To cover the 3 km by 3 km square centered around base station A, we need to cover 1.5 km (1.5 times the hexagon radius toward the right, left, top,and bottom of base station A. this is shown in Figure 3.9. From Figure 3.9, we see that this area contains five base stations. Since each base station has 60 channels, the total number of channels without cell splitting is equal to 5 60=300 channels.

76 Solution (b) with the use of the microcells as shown in Figure3.9 In Figure 3.9 the base station A is surrounded by six microcells. Therefore, the total number of base stations in the squarde area under study is equal to 5+6=11. Since each base station has 60 channels, the total number of channels will be equal to 11 60=660 channels. This is a 2.2 times increase in capacity when compared to case (a).

77 Solution (c) if all the base stations are replaced by microcelles: From Figure 3.9, we see there are a total of 5+12=17 base stations in the square region under study. Since each base station has 60 channels, the total number of channels will be equal to =1020channels. This is a 3.4 times increase in capacity compared to case (a). Theoretically, if all cells were microcells having half the radius of the original cell, the capacity increase would approach four.

78 3.7.2 Sectoring ( R is constant, D/R is decreased ) It increases capacity by keeping the cell radius nuchanged and seek methods to decrease the D/R ratio. It increases SIR so that the cluster size may be reduced and thus increases the frequency reuse. The SIR is improved using directional antenna. By using sectors, the number of interferences in the first tier is reduced from 6 to 2. In practical systems, further improvement in SIR is achieved by down tilting the sector antennas such that the radiation pattern in the vertical (elevation) plane has a notch at the neatest co-channel cell distance. It will increases the number of antennas and it breaks up the available trunked channel pool into several smaller pools, and decreases trunking efficiency.

79

80 3.7.3 Repeaters for Range Extension It needs to provide dedicated coverage for hard-to-reach areas, such as within buildings, or in valleys or tunnels. Repeaters are often used to provide such range extension capabilities. Repeaters are bi-direction, they amplify and reradiate the BS signals. Repeaters do not add capacity to the system. In practice, directional antennas or distributed antenna systems(das) are connected to the inputs or outputs of repeaters for localized spot coverage, particularly in tunnels or buildings. Determining the proper location for repeaters and distributed antenna systems within buildings requires careful planning.

81 3.7.4 A Microcell Zone Concept More than one zone sites (TX/RX) are connected to a single BS and share the same radio equipment. Multiple zones and a single BS make up a cell. Unlike in sectoring, a handoff is not required at MSC when the mobile travels between zones. The BS simply switches the channel to a different zone site. BS radiation is localized and interference is reduced. The advantage is that while the cell maintains a particular coverage radius, CCI is reduced since a large central BS is replaced by several lower powered transmitters. Decreased CCI improves the signal quality and also leads to an increase in capacity without the degradation in trunking efficiency caused by sectoring.

82 微波和光缆电路 微小区选择器 基站 Tx/Rx Tx/Rx Tx/Rx

83 If N=7,SIR=18dB,then it needs D1/R1=4.6. While by using zone microcell concept, D/R=3, N=3. From N=7 to N=3, amounts to a 2.33 times increase in capacity. D D D1 R1 R

Unit-1 The Cellular Concept

Unit-1 The Cellular Concept Unit-1 The Cellular Concept 1.1 Introduction to Cellular Systems Solves the problem of spectral congestion and user capacity. Offer very high capacity in a limited spectrum without major technological

More information

EKT 450 Mobile Communication System

EKT 450 Mobile Communication System EKT 450 Mobile Communication System Chapter 6: The Cellular Concept Dr. Azremi Abdullah Al-Hadi School of Computer and Communication Engineering azremi@unimap.edu.my 1 Introduction Introduction to Cellular

More information

Chapter 3: Cellular concept

Chapter 3: Cellular concept Chapter 3: Cellular concept Introduction to cellular concept: The cellular concept was a major breakthrough in solving the problem of spectral congestion and user capacity. It offered very high capacity

More information

MOBILE COMMUNICATIONS (650520) Part 3

MOBILE COMMUNICATIONS (650520) Part 3 Philadelphia University Faculty of Engineering Communication and Electronics Engineering MOBILE COMMUNICATIONS (650520) Part 3 Dr. Omar R Daoud 1 Trunking and Grade Services Trunking: A means for providing

More information

Chapter 3 Ahmad Bilal ahmadbilal.webs.com

Chapter 3 Ahmad Bilal ahmadbilal.webs.com Chapter 3 A Quick Recap We learned about cell and reuse factor. We looked at traffic capacity We looked at different Earling Formulas We looked at channel strategies We had a look at Handoff Interference

More information

03_57_104_final.fm Page 97 Tuesday, December 4, :17 PM. Problems Problems

03_57_104_final.fm Page 97 Tuesday, December 4, :17 PM. Problems Problems 03_57_104_final.fm Page 97 Tuesday, December 4, 2001 2:17 PM Problems 97 3.9 Problems 3.1 Prove that for a hexagonal geometry, the co-channel reuse ratio is given by Q = 3N, where N = i 2 + ij + j 2. Hint:

More information

ECE 476/ECE 501C/CS Wireless Communication Systems Winter Lecture 3: Cellular Fundamentals

ECE 476/ECE 501C/CS Wireless Communication Systems Winter Lecture 3: Cellular Fundamentals ECE 476/ECE 501C/CS 513 - Wireless Communication Systems Winter 2004 Lecture 3: Cellular Fundamentals Chapter 3 - The Cellular Concept - System Design Fundamentals I. Introduction Goals of a Cellular System

More information

EEG473 Mobile Communications Module 2 : Week # (6) The Cellular Concept System Design Fundamentals

EEG473 Mobile Communications Module 2 : Week # (6) The Cellular Concept System Design Fundamentals EEG473 Mobile Communications Module 2 : Week # (6) The Cellular Concept System Design Fundamentals Interference and System Capacity Interference is the major limiting factor in the performance of cellular

More information

EENG473 Mobile Communications Module 2 : Week # (8) The Cellular Concept System Design Fundamentals

EENG473 Mobile Communications Module 2 : Week # (8) The Cellular Concept System Design Fundamentals EENG473 Mobile Communications Module 2 : Week # (8) The Cellular Concept System Design Fundamentals Improving Capacity in Cellular Systems Cellular design techniques are needed to provide more channels

More information

The Cellular Concept. History of Communication. Frequency Planning. Coverage & Capacity

The Cellular Concept. History of Communication. Frequency Planning. Coverage & Capacity The Cellular Concept History of Communication Frequency Planning Coverage & Capacity Engr. Mian Shahzad Iqbal Lecturer Department of Telecommunication Engineering Before GSM: Mobile Telephony Mile stones

More information

Wireless Communications Principles and Practice 2 nd Edition Prentice-Hall. By Theodore S. Rappaport

Wireless Communications Principles and Practice 2 nd Edition Prentice-Hall. By Theodore S. Rappaport Wireless Communications Principles and Practice 2 nd Edition Prentice-Hall By Theodore S. Rappaport Chapter 3 The Cellular Concept- System Design Fundamentals 3.1 Introduction January, 2004 Spring 2011

More information

Ch3. The Cellular Concept Systems Design Fundamentals. From Rappaport s book

Ch3. The Cellular Concept Systems Design Fundamentals. From Rappaport s book Ch3. The Cellular Concept Systems Design Fundamentals. From Rappaport s book Instructor: Mohammed Taha O. El Astal LOGO Early mobile systems The objective was to achieve a large coverage area by using

More information

A Glimps at Cellular Mobile Radio Communications. Dr. Erhan A. İnce

A Glimps at Cellular Mobile Radio Communications. Dr. Erhan A. İnce A Glimps at Cellular Mobile Radio Communications Dr. Erhan A. İnce 28.03.2012 CELLULAR Cellular refers to communications systems that divide a geographic region into sections, called cells. The purpose

More information

UNIK4230: Mobile Communications Spring Per Hjalmar Lehne Tel:

UNIK4230: Mobile Communications Spring Per Hjalmar Lehne Tel: UNIK4230: Mobile Communications Spring 2015 Per Hjalmar Lehne per-hjalmar.lehne@telenor.com Tel: 916 94 909 Cells and Cellular Traffic (Chapter 4) Date: 12 March 2015 Agenda Introduction Hexagonal Cell

More information

LECTURE 12. Deployment and Traffic Engineering

LECTURE 12. Deployment and Traffic Engineering 1 LECTURE 12 Deployment and Traffic Engineering Cellular Concept 2 Proposed by Bell Labs in 1971 Geographic Service divided into smaller cells Neighboring cells do not use same set of frequencies to prevent

More information

ECS 445: Mobile Communications The Cellular Concept

ECS 445: Mobile Communications The Cellular Concept Sirindhorn International Institute of Technology Thammasat University School of Information, Computer and Communication Technology ECS 445: Mobile Communications The Cellular Concept Prapun Suksompong,

More information

Chapter 1 Introduction to Mobile Computing (16 M)

Chapter 1 Introduction to Mobile Computing (16 M) Chapter 1 Introduction to Mobile Computing (16 M) 1.1 Introduction to Mobile Computing- Mobile Computing Functions, Mobile Computing Devices, Mobile Computing Architecture, Evolution of Wireless Technology.

More information

ETI2511-WIRELESS COMMUNICATION II HANDOUT I 1.0 PRINCIPLES OF CELLULAR COMMUNICATION

ETI2511-WIRELESS COMMUNICATION II HANDOUT I 1.0 PRINCIPLES OF CELLULAR COMMUNICATION ETI2511-WIRELESS COMMUNICATION II HANDOUT I 1.0 PRINCIPLES OF CELLULAR COMMUNICATION 1.0 Introduction The substitution of a single high power Base Transmitter Stations (BTS) by several low BTSs to support

More information

UNIK4230: Mobile Communications. Abul Kaosher

UNIK4230: Mobile Communications. Abul Kaosher UNIK4230: Mobile Communications Abul Kaosher abul.kaosher@nsn.com Cells and Cellular Traffic Cells and Cellular Traffic Introduction Hexagonal Cell Geometry Co-Channel Interference (CCI) CCI Reduction

More information

UNIK4230: Mobile Communications Spring 2013

UNIK4230: Mobile Communications Spring 2013 UNIK4230: Mobile Communications Spring 2013 Abul Kaosher abul.kaosher@nsn.com Mobile: 99 27 10 19 1 UNIK4230: Mobile Communications Cells and Cellular Traffic- I Date: 07.03.2013 2 UNIK4230: Mobile Communications

More information

The Cellular Concept System Design Fundamentals

The Cellular Concept System Design Fundamentals Wireless Information Transmission System Lab. The Cellular Concept System Design Fundamentals Institute of Communications Engineering National Sun Yat-sen University Table of Contents Frequency Reuse Channel

More information

Unit 2: Mobile Communication Systems Lecture 8, 9: Performance Improvement Techniques in Cellular Systems. Today s Lecture: Outline

Unit 2: Mobile Communication Systems Lecture 8, 9: Performance Improvement Techniques in Cellular Systems. Today s Lecture: Outline Unit 2: Mobile Communication Systems Lecture 8, 9: Performance Improvement Techniques in Cellular Systems Today s Lecture: Outline Handover & Roaming Hard and Soft Handover Power Control Cell Splitting

More information

Cellular Concept. Cell structure

Cellular Concept. Cell structure Cellular Concept Dr Yousef Dama Faculty of Engineering and Information Technology An-Najah National University 2014-2015 Mobile communications Lecture Notes, prepared by Dr Yousef Dama, An-Najah National

More information

ECS455 Chapter 2 Cellular Systems

ECS455 Chapter 2 Cellular Systems ECS455 Chapter 2 Cellular Systems 2.4 Traffic Handling Capacity and Erlang B Formula 1 Dr.Prapun Suksompong prapun.com/ecs455 Capacity Concept: A Revisit Q: If I have m channels per cell, is it true that

More information

UNIT-II 1. Explain the concept of frequency reuse channels. Answer:

UNIT-II 1. Explain the concept of frequency reuse channels. Answer: UNIT-II 1. Explain the concept of frequency reuse channels. Concept of Frequency Reuse Channels: A radio channel consists of a pair of frequencies one for each direction of transmission that is used for

More information

Chapter 1 Introduction to Mobile Computing

Chapter 1 Introduction to Mobile Computing Chapter 1 Introduction to Mobile Computing 1.1 Introduction to Mobile Computing- Mobile Computing Functions, Mobile Computing Devices, Mobile Computing Architecture, Evolution of Wireless Technology. 1.2

More information

GTBIT ECE Department Wireless Communication

GTBIT ECE Department Wireless Communication Q-1 What is Simulcast Paging system? Ans-1 A Simulcast Paging system refers to a system where coverage is continuous over a geographic area serviced by more than one paging transmitter. In this type of

More information

2016/10/14. YU Xiangyu

2016/10/14. YU Xiangyu 2016/10/14 YU Xiangyu yuxy@scut.edu.cn Structure of Mobile Communication System Cell Handover/Handoff Roaming Mobile Telephone Switching Office Public Switched Telephone Network Tomasi Advanced Electronic

More information

EMF Safety and Actions in China Telecom

EMF Safety and Actions in China Telecom 4 th ITU Green Standards Week EMF Safety and Actions in China Telecom Tan Rumeng China Telecommunications Corp. 25 September 2014 Outline 31 Background 2 EMF safety in China 3 EMF actions in China Telecom

More information

Cellular Concept MSC. Wireless Communications, CIIT Islamabad. Cellular Concept

Cellular Concept MSC. Wireless Communications, CIIT Islamabad. Cellular Concept Cellular Concept Course Instructor: Dr. Syed Junaid Nawaz Assistant Professor, Dept. of Electrical Engineering, COMSATS Institute of IT, Islamabad, Pakistan. Email: junaidnawaz@ieee.org Courtesy of: Prof.

More information

Mobile & Wireless Networking. Lecture 4: Cellular Concepts & Dealing with Mobility. [Reader, Part 3 & 4]

Mobile & Wireless Networking. Lecture 4: Cellular Concepts & Dealing with Mobility. [Reader, Part 3 & 4] 192620010 Mobile & Wireless Networking Lecture 4: Cellular Concepts & Dealing with Mobility [Reader, Part 3 & 4] Geert Heijenk Outline of Lecture 4 Cellular Concepts q Introduction q Cell layout q Interference

More information

Introduction to Wireless and Mobile Networking. Hung-Yu Wei g National Taiwan University

Introduction to Wireless and Mobile Networking. Hung-Yu Wei g National Taiwan University Introduction to Wireless and Mobile Networking Lecture 3: Multiplexing, Multiple Access, and Frequency Reuse Hung-Yu Wei g National Taiwan University Multiplexing/Multiple Access Multiplexing Multiplexing

More information

Chapter 3 Cellular Concept

Chapter 3 Cellular Concept Chapter 3 Cellular Concept 6 3 7 3 5 6 7 6 7 7 5 Objectives To resolve spectral congestion and user capacity To provide additional radio capacity radio capacity with no additional increase in radio Methods

More information

ECE 5325/6325: Wireless Communication Systems Lecture Notes, Fall Increasing Capacity and Coverage. Lecture 4

ECE 5325/6325: Wireless Communication Systems Lecture Notes, Fall Increasing Capacity and Coverage. Lecture 4 ECE 5325/6325: Wireless Communication Systems Lecture Notes, Fall 2011 Lecture 4 Today: (1) Sectoring (2) Cell Splitting Reading today: 3.7; Tue: 4.1-4.3, 4.9. HW 1 due Friday 10am in HW locker (#3). Please

More information

Wireless Cellular Networks. Base Station - Mobile Network

Wireless Cellular Networks. Base Station - Mobile Network Wireless Cellular Networks introduction frequency reuse channel assignment strategies techniques to increase capacity handoff cellular standards 1 Base Station - Mobile Network RCC RVC FVC FCC Forward

More information

Data and Computer Communications. Chapter 10 Cellular Wireless Networks

Data and Computer Communications. Chapter 10 Cellular Wireless Networks Data and Computer Communications Chapter 10 Cellular Wireless Networks Cellular Wireless Networks 5 PSTN Switch Mobile Telecomm Switching Office (MTSO) 3 4 2 1 Base Station 0 2016-08-30 2 Cellular Wireless

More information

Mixed Frequency Allocation Strategy for GSM-R

Mixed Frequency Allocation Strategy for GSM-R Mixed Frequency Allocation Strategy for GSM-R Xiao-Li Jiang, Xu Li State Key Laboratory of Rail Traffic Control and Safety (Beijing Jiaotong University), Beijing, 100044, China Abstract: In this paper,

More information

SNS COLLEGE OF ENGINEERING COIMBATORE DEPARTMENT OF INFORMATION TECHNOLOGY QUESTION BANK

SNS COLLEGE OF ENGINEERING COIMBATORE DEPARTMENT OF INFORMATION TECHNOLOGY QUESTION BANK SNS COLLEGE OF ENGINEERING COIMBATORE 641107 DEPARTMENT OF INFORMATION TECHNOLOGY QUESTION BANK EC6801 WIRELESS COMMUNICATION UNIT-I WIRELESS CHANNELS PART-A 1. What is propagation model? 2. What are the

More information

MOBILE COMMUNICATIONS (650539) Part 3

MOBILE COMMUNICATIONS (650539) Part 3 Philadelphia University Faculty of Engineering Communication and Electronics Engineering MOBILE COMMUNICATIONS (650539) Part 3 Dr. Omar R Daoud ١ The accommodation of larger number of users in a limited

More information

SLIDE #2.1. MOBILE COMPUTING NIT Agartala, Dept of CSE Jan-May,2012. ALAK ROY. Assistant Professor Dept. of CSE NIT Agartala

SLIDE #2.1. MOBILE COMPUTING NIT Agartala, Dept of CSE Jan-May,2012. ALAK ROY. Assistant Professor Dept. of CSE NIT Agartala Mobile Cellular Systems SLIDE #2.1 MOBILE COMPUTING NIT Agartala, Dept of CSE Jan-May,2012 ALAK ROY. Assistant Professor Dept. of CSE NIT Agartala Email-alakroy.nerist@gmail.com What we will learn in this

More information

Electromagnetic Interference Compatibility for Mobile Communication System. Abstract

Electromagnetic Interference Compatibility for Mobile Communication System. Abstract Commission E: Electromagnetic Noise and Interference (e) Scientific basis of noise and interference control Electromagnetic Interference Compatibility for Mobile Communication System M.K Raina, Kirti Gupta

More information

Mobile Communication Systems

Mobile Communication Systems Mobile Communication Systems Part II- Traffic Engineering Professor Z Ghassemlooy Electronics & IT Division Scholl of Engineering, Sheffield Hallam University U.K. www.shu.ac.uk/ocr Contents Problems +

More information

Cellular Wireless Networks. Chapter 10

Cellular Wireless Networks. Chapter 10 Cellular Wireless Networks Chapter 10 Cellular Network Organization Use multiple low-power transmitters (100 W or less) Areas divided into cells Each cell is served by base station consisting of transmitter,

More information

Cellular Wireless Networks and GSM Architecture. S.M. Riazul Islam, PhD

Cellular Wireless Networks and GSM Architecture. S.M. Riazul Islam, PhD Cellular Wireless Networks and GSM Architecture S.M. Riazul Islam, PhD Desirable Features More Capacity Less Power Larger Coverage Cellular Network Organization Multiple low power transmitters 100w or

More information

Figure 1.1:- Representation of a transmitter s Cell

Figure 1.1:- Representation of a transmitter s Cell Volume 4, Issue 2, February 2014 ISSN: 2277 128X International Journal of Advanced Research in Computer Science and Software Engineering Research Paper Available online at: www.ijarcsse.com Study on Improving

More information

GSM FREQUENCY PLANNING

GSM FREQUENCY PLANNING GSM FREQUENCY PLANNING PROJECT NUMBER: PRJ070 BY NAME: MUTONGA JACKSON WAMBUA REG NO.: F17/2098/2004 SUPERVISOR: DR. CYRUS WEKESA EXAMINER: DR. MAURICE MANG OLI Introduction GSM is a cellular mobile network

More information

Page 1. Problems with 1G Systems. Wireless Wide Area Networks (WWANs) EEC173B/ECS152C, Spring Cellular Wireless Network

Page 1. Problems with 1G Systems. Wireless Wide Area Networks (WWANs) EEC173B/ECS152C, Spring Cellular Wireless Network EEC173B/ECS152C, Spring 2009 Wireless Wide Area Networks (WWANs) Cellular Wireless Network Architecture and Protocols Applying concepts learned in first two weeks: Frequency planning, channel allocation

More information

Communication Switching Techniques

Communication Switching Techniques Communication Switching Techniques UNIT 5 P.M.Arun Kumar, Assistant Professor, Department of IT, Sri Krishna College of Engineering and Technology, Coimbatore. PRINCIPLES OF CELLULAR NETWORKS TOPICS TO

More information

CMC VIDYA SAGAR P. UNIT IV FREQUENCY MANAGEMENT AND CHANNEL ASSIGNMENT Numbering and grouping, Setup access and paging

CMC VIDYA SAGAR P. UNIT IV FREQUENCY MANAGEMENT AND CHANNEL ASSIGNMENT Numbering and grouping, Setup access and paging UNIT IV FREQUENCY MANAGEMENT AND CHANNEL ASSIGNMENT Numbering and grouping, Setup access and paging channels, Channel assignments to cell sites and mobile units, Channel sharing and barrowing, sectorization,

More information

Data and Computer Communications

Data and Computer Communications Data and Computer Communications Chapter 14 Cellular Wireless Networks Eighth Edition by William Stallings Cellular Wireless Networks key technology for mobiles, wireless nets etc developed to increase

More information

MSIT 413: Wireless Technologies Week 2

MSIT 413: Wireless Technologies Week 2 MSIT 413: Wireless Technologies Week 2 Michael L. Honig Department of EECS Northwestern University September 2017 1 Wireless Standards: Our Focus Cellular LAN MAN PAN Sensor/IoT GSM CDMA2000 WCDMA UMTS

More information

ECE 5325/6325: Wireless Communication Systems Lecture Notes, Spring 2010

ECE 5325/6325: Wireless Communication Systems Lecture Notes, Spring 2010 ECE 5325/6325: Wireless Communication Systems Lecture Notes, Spring 2010 Lecture 2 Today: (1) Frequency Reuse, (2) Handoff Reading for today s lecture: 3.2-3.5 Reading for next lecture: Rap 3.6 HW 1 will

More information

Chapter 5 The Cellular Concept

Chapter 5 The Cellular Concept hapter 5 The ellular oncept 1 ell Shape Actual cell/ideal cell Signal Strength Handoff egion ell apacity Traffic theory Erlang B and Erlang ell Structure Frequency euse euse Distance ochannel Interference

More information

The Cellular Concept

The Cellular Concept The Cellular Concept Key problems in multi-user wireless system: spectrum is limited and expensive large # of users to accommodate high quality-of-services (QoS) is required expandable systems are needed

More information

Unit 4 - Cellular System Design, Capacity, Handoff, and Outage

Unit 4 - Cellular System Design, Capacity, Handoff, and Outage Unit 4 - Cellular System Design, Capacity, Handoff, and Outage Course outline How to access the portal Assignment. Overview of Cellular Evolution and Wireless Technologies Wireless Propagation and Cellular

More information

ECS455 Chapter 2 Cellular Systems

ECS455 Chapter 2 Cellular Systems ECS455 Chapter 2 Cellular Systems 2.2 Co-Channel Interference r.rapun Suksompong prapun.com/ecs455 Office Hours: BK 360-7 Tuesday 9:30-0:30 Tuesday 3:30-4:30 Thursday 3:30-4:30 Co-Channel Cells: Ex. N

More information

UNIT- 3. Introduction. The cellular advantage. Cellular hierarchy

UNIT- 3. Introduction. The cellular advantage. Cellular hierarchy UNIT- 3 Introduction Capacity expansion techniques include the splitting or sectoring of cells and the overlay of smaller cell clusters over larger clusters as demand and technology increases. The cellular

More information

2.4 OPERATION OF CELLULAR SYSTEMS

2.4 OPERATION OF CELLULAR SYSTEMS INTRODUCTION TO CELLULAR SYSTEMS 41 a no-traffic spot in a city. In this case, no automotive ignition noise is involved, and no cochannel operation is in the proximity of the idle-channel receiver. We

More information

SEN366 (SEN374) (Introduction to) Computer Networks

SEN366 (SEN374) (Introduction to) Computer Networks SEN366 (SEN374) (Introduction to) Computer Networks Prof. Dr. Hasan Hüseyin BALIK (8 th Week) Cellular Wireless Network 8.Outline Principles of Cellular Networks Cellular Network Generations LTE-Advanced

More information

M Y R E V E A L - C E L L U L A R

M Y R E V E A L - C E L L U L A R M Y R E V E A L - C E L L U L A R The hexagon cell shape If we have two BTSs with omniantennas and we require that the border between the coverage area of each BTS is the set of points where the signal

More information

Chapter 8 Traffic Channel Allocation

Chapter 8 Traffic Channel Allocation Chapter 8 Traffic Channel Allocation Prof. Chih-Cheng Tseng tsengcc@niu.edu.tw http://wcnlab.niu.edu.tw EE of NIU Chih-Cheng Tseng 1 Introduction What is channel allocation? It covers how a BS should assign

More information

Downlink Erlang Capacity of Cellular OFDMA

Downlink Erlang Capacity of Cellular OFDMA Downlink Erlang Capacity of Cellular OFDMA Gauri Joshi, Harshad Maral, Abhay Karandikar Department of Electrical Engineering Indian Institute of Technology Bombay Powai, Mumbai, India 400076. Email: gaurijoshi@iitb.ac.in,

More information

Level 6 Graduate Diploma in Engineering Wireless and mobile communications

Level 6 Graduate Diploma in Engineering Wireless and mobile communications 9210-119 Level 6 Graduate Diploma in Engineering Wireless and mobile communications Sample Paper You should have the following for this examination one answer book non-programmable calculator pen, pencil,

More information

Data and Computer Communications. Tenth Edition by William Stallings

Data and Computer Communications. Tenth Edition by William Stallings Data and Computer Communications Tenth Edition by William Stallings Data and Computer Communications, Tenth Edition by William Stallings, (c) Pearson Education - 2013 CHAPTER 10 Cellular Wireless Network

More information

King Fahd University of Petroleum & Minerals Computer Engineering Dept

King Fahd University of Petroleum & Minerals Computer Engineering Dept King Fahd University of Petroleum & Minerals Computer Engineering Dept COE 543 Mobile and Wireless Networks Term 0 Dr. Ashraf S. Hasan Mahmoud Rm -148-3 Ext. 174 Email: ashraf@ccse.kfupm.edu.sa 4//003

More information

Chapter 2 Cellular Wireless Communication

Chapter 2 Cellular Wireless Communication Chapter 2 Cellular Wireless Communication 2.1 Introduction Originally, the focus of mobile radio systems design was towards increasing the coverage of a single transceiver. A single powerful base station

More information

FTP10N40/FTA10N40 400V N 沟道 MOS 场效应管. 产品特点 低的导通电阻 低的栅极电荷 ( 典型值为 34nC) 开关速度快 100% 雪崩测试 符合 RoHS 标准 / 无铅封装 产品应用 高效开关电源 适配器 / 充电器 有源功率因数校正 液晶面板电源 订购代码

FTP10N40/FTA10N40 400V N 沟道 MOS 场效应管. 产品特点 低的导通电阻 低的栅极电荷 ( 典型值为 34nC) 开关速度快 100% 雪崩测试 符合 RoHS 标准 / 无铅封装 产品应用 高效开关电源 适配器 / 充电器 有源功率因数校正 液晶面板电源 订购代码 400V N 沟道 MOS 场效应管 产品特点 低的导通电阻 低的栅极电荷 ( 典型值为 34nC) 开关速度快 00% 雪崩测试 符合 RoHS 标准 / 无铅封装 BV DSS R DS(ON) (Max.) I D 400V 0.50Ω 0A 产品应用 高效开关电源 适配器 / 充电器 有源功率因数校正 液晶面板电源 订购代码 器件型号封装形式标识 FTP0N40 TO-220 FTP0N40

More information

Multi-Channel CMOS Front-End IC for Physiological Signal Acquisition 生理信号采集的多通道 CMOS 模拟前端集成电路设计 张金勇王磊于力

Multi-Channel CMOS Front-End IC for Physiological Signal Acquisition 生理信号采集的多通道 CMOS 模拟前端集成电路设计 张金勇王磊于力 Vol 3 No9 / Sep 29 CMOS Front-End IC for Physiological Signal Acquisition 生理信号采集的多通道 CMOS 模拟前端集成电路设计 张金勇王磊于力 ABSTRACT A compacted and low-offset multi-channel CMOS front-end IC for physiological signal

More information

(Refer Slide Time: 00:01:29 min)

(Refer Slide Time: 00:01:29 min) Wireless Communications Dr. Ranjan Bose Department of Electrical Engineering Indian Institute of Technology, Delhi Lecture No. # 5 Cell Capacity and Reuse We ll look at some the interesting features of

More information

CHAPTER 2. Instructor: Mr. Abhijit Parmar Course: Mobile Computing and Wireless Communication ( )

CHAPTER 2. Instructor: Mr. Abhijit Parmar Course: Mobile Computing and Wireless Communication ( ) CHAPTER 2 Instructor: Mr. Abhijit Parmar Course: Mobile Computing and Wireless Communication (2170710) Syllabus Chapter-2.1 Cellular Wireless Networks 2.1.1 Principles of Cellular Networks Underlying technology

More information

1. Classify the mobile radio transmission systems. Simplex & Duplex. 2. State example for a half duplex system. Push to talk and release to listen.

1. Classify the mobile radio transmission systems. Simplex & Duplex. 2. State example for a half duplex system. Push to talk and release to listen. 1. Classify the mobile radio transmission systems. Simplex & Duplex. 2. State example for a half duplex system. Push to talk and release to listen. 3. State example for a Simplex system. Pager. 4. State

More information

RHT03-SPI Temperature & Humidity Sensor

RHT03-SPI Temperature & Humidity Sensor - Relative humidity and temperature sensor - 相对温度和湿度传感器 - Pre-calculated temperature and humidity read out, no extra calculation needed - 预先计算的温度和湿度读出, 无需额外计算 - Dew Point Calculation possible - 可以计算露点

More information

Prof. Zygmunt J. Haas 1

Prof. Zygmunt J. Haas 1 Wireless Networks Spring 2013 Part #1: Introduction to Wireless Communication Systems and Networks Goals: Introduce the basic concepts of a Wireless System Understand the basic operation of a cellular

More information

CELLULAR AND MOBILE COMMUNICATIONS

CELLULAR AND MOBILE COMMUNICATIONS CELLULAR AND MOBILE COMMUNICATIONS by VIDYA SAGAR POTHARAJU Associate Professor, Dept of ECE,. 1 TEXT BOOKS 1.Mobile and Cellular Telecommunications-W.C.Y.Lee 2 nd Edn, 1989. 2. Wireless Communications-Theodre.S.Rapport,

More information

College of Engineering

College of Engineering WiFi and WCDMA Network Design Robert Akl, D.Sc. College of Engineering Department of Computer Science and Engineering Outline WiFi Access point selection Traffic balancing Multi-Cell WCDMA with Multiple

More information

ADJACENT BAND COMPATIBILITY OF 400 MHZ TETRA AND ANALOGUE FM PMR AN ANALYSIS COMPLETED USING A MONTE CARLO BASED SIMULATION TOOL

ADJACENT BAND COMPATIBILITY OF 400 MHZ TETRA AND ANALOGUE FM PMR AN ANALYSIS COMPLETED USING A MONTE CARLO BASED SIMULATION TOOL European Radiocommunications Committee (ERC) within the European Conference of Postal and Telecommunications Administrations (CEPT) ADJACENT BAND COMPATIBILITY OF 400 MHZ AND ANALOGUE FM PMR AN ANALYSIS

More information

Version:2.0 M1+/M2/M3

Version:2.0 M1+/M2/M3 Version:2.0 M1+/M2/M3 Safety Information CAUTION: To reduce the risk of electric shock, do not remove any cover(or the rear section). No user serviceable parts inside. Refer servicing to qualified service

More information

CS Mobile and Wireless Networking Homework 1

CS Mobile and Wireless Networking Homework 1 S 515 - Mobile and Wireless Networking Homework 1 ate: Oct 16, 2002, Wednesday You may benefit from the following tools if you wish: scientific calculator function plotter like matlab, gnuplot, or any

More information

CCAP: A Strategic Tool for Managing Capacity of CDMA Networks

CCAP: A Strategic Tool for Managing Capacity of CDMA Networks CCAP: A Strategic Tool for Managing Capacity of CDMA Networks Teleware Co. Ltd. in cooperation with Washington University, Saint Louis, Missouri, USA What is CCAP Graphical interactive tool for CDMA Calculates

More information

1 st 5G Algorithm Competition SCMA

1 st 5G Algorithm Competition SCMA 1 st 5G Algorithm Competition SCMA Task Description Requirements 要求 : SCMA 下一代无线通信的稀疏码多址接入 多址接入是无线通信物理层最核心的技术之一, 它使得无线基站能区分并同时服务多个终端用户 现有系统采用正交的多址接入方式, 即多个用户通过在不同维度上 ( 频分 时分 码分等 ) 正交划分的资源来接入, 现在 4G 系统中采用的

More information

NX70 Installation Instructions High Performance Pulse Output Counter Module

NX70 Installation Instructions High Performance Pulse Output Counter Module Maximum Value for OEMs SM NX70 Installation Instructions High Performance Pulse Output Counter Module Catalog Number: NX70-PULSE4 Contents English... 3 Chinese... 19 English Contents Important User Information...4

More information

WiMAX 技术培训系列 ( 一 ) OFDM 物理层技术初探 MCG 赵昕 2006 年 2 月. All rights reserved 2006, Alcatel Shanghai Bell

WiMAX 技术培训系列 ( 一 ) OFDM 物理层技术初探 MCG 赵昕 2006 年 2 月. All rights reserved 2006, Alcatel Shanghai Bell WiMAX 技术培训系列 ( 一 ) OFDM 物理层技术初探 MCG 赵昕 2006 年 2 月 目录 Page 2 一. 为什么出现 WiMAX? 二. 什么是 WiMAX? 三. 什么是 OFDM/OFDMA? 四.WiMAX 的 PHY 层五.WiMAX 接入过程 Page 3 一. 为什么出现 WiMAX? 一. 为什么出现 WiMAX? 移动通信的发展过程正在从 3Any 向 Olympics

More information

EENG473 Mobile Communications Module 2 : Week # (4) The Cellular Concept System Design Fundamentals

EENG473 Mobile Communications Module 2 : Week # (4) The Cellular Concept System Design Fundamentals EENG473 Mobile Communications Module 2 : Week # (4) The Cellular Concept System Design Fundamentals Frequency reuse or frequency planning : The design process of selecting and allocating channel groups

More information

ECE 5325/6325: Wireless Communication Systems Lecture Notes, Spring 2013

ECE 5325/6325: Wireless Communication Systems Lecture Notes, Spring 2013 ECE 5325/6325: Wireless Communication Systems Lecture Notes, Spring 2013 Lecture 3 Today: (2) Trunking Reading: Today: 4.2.2. Thu: Rap 3.7.2 (pdf on Canvas). 1 Trunking Trunking refers to sharing few channels

More information

Cellular Network. Ir. Muhamad Asvial, MSc., PhD

Cellular Network. Ir. Muhamad Asvial, MSc., PhD Cellular Network Ir. Muhamad Asvial, MSc., PhD Center for Information and Communication Engineering Research (CICER) Electrical Engineering Department - University of Indonesia E-mail: asvial@ee.ui.ac.id

More information

Cellular Mobile Radio Networks Design

Cellular Mobile Radio Networks Design Cellular Mobile Radio Networks Design Yu-Cheng Chang Ph. D. Candidate, Department of Technology Management Chung Hua University, CHU Hsinchu, Taiwan d09603024@chu.edu.tw Chi-Yuan Chang CMC Consulting,

More information

US SEALED SERIES. Structure. Features 特点. Connector M Connector F

US SEALED SERIES. Structure. Features 特点. Connector M Connector F US SEALED SERIES Structure Connector M Connector F Features 特点 Housing Housing TPA TPA Terminal Terminal Wire Seal Wire Seal US sealed series comply with SAE/USCAR-2. This series consits of 0.64mm, 1.5mm,

More information

¼'' TS 法律声明 10. MUSIC Tribe

¼'' TS 法律声明 10. MUSIC Tribe NEUTRON Paraphonic Analog and Semi-Modular Synthesizer with Dual 3340 VCOs, Multi-Mode VCF, 2 ADSRs, BBD Delay and Overdrive Circuit in a Eurorack Format 2 NEUTRON 快速启动向导 3 重要的安全须知 ¼'' TS 1. 2. 3. 4. 5.

More information

ECS455 Chapter 2 Cellular Systems

ECS455 Chapter 2 Cellular Systems ECS455 Chapter 2 Cellular Systems 2.3 Sectoring 1 Dr.Prapun Suksompong prapun.com/ecs455 C A Improving Coverage and Capacity As the demand for wireless service increases, the number of channels assigned

More information

NX70 Installation Instructions High Speed Counter Module

NX70 Installation Instructions High Speed Counter Module Maximum Value for OEMs SM NX70 Installation Instructions High Speed Counter Module Catalog Number: NX70-HSC1, NX70-HSC2 Contents English... 3 Chinese... 23 English Contents Important User Information...4

More information

YP G-HSD Hall Current Sensor 确保测量准确精度高 安装方便 售价低. 执行标准 Standard 过载能力 Overload 精度 Accuracy 线性度 Linearity 失调电压 Voltage maladjustment

YP G-HSD Hall Current Sensor 确保测量准确精度高 安装方便 售价低. 执行标准 Standard 过载能力 Overload 精度 Accuracy 线性度 Linearity 失调电压 Voltage maladjustment YPG-HSD YP G-HSD Hall Current Sensor Model Description YPG - HSD - 外形代号 (Externality Code) - 额定电流 (Rated Current) HSD 外形代号 Externality Code 霍尔效应直检式传感器 Hall Effect Current Sensor & Transducer 1~7 ( 见外形图

More information

Wireless Communication Technologies (16:332:546)

Wireless Communication Technologies (16:332:546) Wireless Communication Technologies (16:332:546) Taught by Professor Narayan Mandayam Lecture 7 : Co-Channel Interference Slides prepared by : Shuangyu Luo Outline Co-channel interference 4 Examples of

More information

8 English P.20 한국의 P.21 中 文 P.22

8 English P.20 한국의 P.21 中 文 P.22 8 English P. 20 한국의 P. 21 中文 P. 22 인터넷 시스템 이용가이드 络 统 0120-615-919 support@broad-e.co.jp http://b-cubic.com/user/ 英 :If you have any inquiries about settings or connection please contact the Internet

More information

M030 and M040. Operating Manual Genelec M030 and M040 Active Monitoring Loudspeakers 操作手册

M030 and M040. Operating Manual Genelec M030 and M040 Active Monitoring Loudspeakers 操作手册 M030 and M040 Operating Manual Genelec M030 and M040 ctive Monitoring Loudspeakers 操作手册 Quick setup guide 快速设置指南 M030 / M040 Speaker Placement 音箱的摆放 Vertical ngle 垂直方向的角度 L 30 C R L C R 110 LS RS RS LS

More information

Multiple access and cellular systems

Multiple access and cellular systems RADIO SYSTEMS ETIN15 Lecture no: 9 Multiple access and cellular systems 2017-05-02 Anders J Johansson 1 Contents Background Interference and spectrum efficiency Frequency-division multiple access (FDMA)

More information

Introduction to Wireless Communications

Introduction to Wireless Communications Wireless Information Transmission System Lab. Introduction to Wireless Communications Institute of Communications Engineering National Sun Yat-sen University Wireless Communication Systems Network Radio

More information

Wireless WANS and MANS. Chapter 3

Wireless WANS and MANS. Chapter 3 Wireless WANS and MANS Chapter 3 Cellular Network Concept Use multiple low-power transmitters (100 W or less) Areas divided into cells Each served by its own antenna Served by base station consisting of

More information

Table of Contents. DS177-ZH LUXEON V2 Product Datasheet Lumileds Holding B.V. All rights reserved.

Table of Contents. DS177-ZH LUXEON V2 Product Datasheet Lumileds Holding B.V. All rights reserved. Illumination LUXEON V2 卓越性能 更多可用光 久经验证的封装 设计 LUXEON V2 是一种基于芯片级封装 (CSP 的高功率圆顶 LED 针对定向应用 进行了优化 传承了 Lumileds 在同类产品中的领先地位 LUXEON V2 具备 优越的效能和稳健性 采用 3 条式 3535 封装 可通过与 LUXEON TX 辐射模 式相匹配加快产品的上市时间 同时通过在更高驱动电流下提供无与伦比的

More information

(8+8) 6. (a) Explain the following in detail concern to the mobile system?

(8+8) 6. (a) Explain the following in detail concern to the mobile system? SET - 1 1. (a) Explain the operation of the cellular system? (b) Discuss analog cellular systems (AMPS) in detail? 2. (a) What is meant by frequency reuse? Explain various frequency reuse schemes and find

More information

ECE6604 PERSONAL & MOBILE COMMUNICATIONS. Week 2. Interference and Shadow Margins, Handoff Gain, Coverage Capacity, Flat Fading

ECE6604 PERSONAL & MOBILE COMMUNICATIONS. Week 2. Interference and Shadow Margins, Handoff Gain, Coverage Capacity, Flat Fading ECE6604 PERSONAL & MOBILE COMMUNICATIONS Week 2 Interference and Shadow Margins, Handoff Gain, Coverage Capacity, Flat Fading 1 Interference Margin As the subscriber load increases, additional interference

More information