Telecommunications Regulation & Trends Lectures 2-4: Spectrum Management Fundamentals

Transcription

1 Telecommunications Regulation & Trends Lectures 2-4: Spectrum Management Fundamentals ) ديغم فاضل ( Digham Dr. Fadel R&D Executive Director National Telecom Regulatory Authority (NTRA), Egypt

2 The radio spectrum is a subset of the electromagnetic waves lying between the frequencies from 9 khz to 300 GHz. Radio Spectrum Source: Ofcom 2

3 In general, signals sent using the higher frequencies have lower propagation distances but a higher data-carrying capacity Free Space Path Loss is proportional to d 2 f 2 These physical characteristics of the spectrum limit the currently identified range of applications for which any particular band is suitable. 3

4 4

5 Radio Spectrum In the past, radio spectrum has been highly regulated to protect against interference (defense, public interests, security) delayed, in some cases, the introduction and growth of a variety of beneficial technologies and services, or increased the cost of the same through an artificial scarcity The demand for spectrum has grown significantly highlighting the need for efficient use of all available spectrum in order to avoid scarcity 5

6 Key Definitions Spectrum Allocation : setting out what radio services can use which frequency bands and under what conditions (National Frequency Allocation Table). Allocation: distribution of frequencies to radio services (on a primary or on a secondary basis) 6 Spectrum Resource Usage: Spectrum is used as an input into a multitude of services: - Communications services: narrow or broadband mobile telecommunications, broadcasting, aeronautical and marine communications, and communications for public bodies such as defense or emergency services. - Non-communication uses: military and civilian radar, scientific applications such as astronomy and so on.

7 Key Definitions Frequency Allotment : entries of designated channels in a plan used by one or more identified countries or geographical areas, for terrestrial or space radio communication service(s) under specified conditions. Allotment: distribution of frequencies to geographical areas or countries Frequency Assignment : authorizations given to users or radio stations to use radio frequencies or radio frequency channels under specified conditions. Assignment: distribution of frequencies to users or radio stations. 7

8 Spectrum Management System Spectrum management is the overall process of regulating and administering the use of the RF spectrum. It is a combination of Administrative and technical procedures to ensure the efficient operation of radio communication equipment and services in compliance with certain rules and etiquettes. It takes place at two levels: National and International. 8

9 Spectrum Management System Granting users/operators access to spectrum Granting equipment access under certain conditions Authorization Planning Allocation of portions of the frequency spectrum to specified uses Monitoring of the use of the radio spectrum and the implementation of measures to control unauthorized use. Monitoring & Compliance Engineering Development of electromagnetic compatibility standards for equipment that emits or is susceptible to radio frequencies 9

10 10 Spectrum Planning

11 It means: Spectrum Planning Why: Developing and implementing spectrum management tools, techniques, and polices to introduce efficient spectrum utilization. To let the regulators prepare an appropriate response for the future events. To meet the growth in spectrum demand. To achieve the social and economic importance of spectrum use. 11

12 Considerations in planning Public Benefits Access by radio is easy than wired Service reaches with high quality Social and economic importance Impact of new tech. Technical Compatibility with other services Bandwidth required Minimum signal strength Other Considerations No national boundaries for radio waves propagation. Spectrum is available equally in every country. Radio systems operate on a world-wide basis. International cooperation is needed. Radio regulations contain provisions for all radio services. Practical antenna ch/s Propagation ch/s Acceptable Interference Level Receiver complexity, and availability 12

13 Technical Consideration Examples Types of Communications Duplex Simplex Communication: One-way communication Half-duplex Communication: Two-way communication but not simultaneous (Push-to-talk) Full-duplex Communication: Two-way communication simultaneously FDD & TDD 13

14 power power power Technical Consideration Examples Multiple Access Schemes FDMA/OFDMA TDMA CDMA 14

15 Frequency Allocation

16 The Spectrum Chart in Egypt

17 Spectrum Authorization (or Assignment) 17

18 Spectrum Authorization/Assignment Schemes Spectrum Assignment Schemes Licensed Unlicensed (Non-Exclusive) Commons (Non-Exclusive) Command & Control (Exclusive) Spectrum Trading (Non-Exclusive)

19 Spectrum Authorization/Assignment Schemes Licensed vs. Unlicensed > Licensed: allocated for fee (auctioning for example as in the mobile case) > Unlicensed: free access (as in the WiFi case) Exclusive vs. Non-Exclusive use: > Command and control classical approach: dedicated for specific users for specific purposes with interference-free guarantee > Commons (shared access): common pool of frequencies > Secondary market (tradable spectrum): a primary spectrum holder can resell or lease its spectrum to a secondary operator/user

20 Licensing Function Aim: Issuing a licensing to operate a transmitter under specified conditions will minimize interference Examine applications of licenses for eligibility and technical compliance with equipment standard. Grant authorization to use national allocation table Issue licenses and collect fees Review, renew or cancel licenses Ensure the technical parameters mentioned in the license. 20

21 Licensing Function Historically, licenses have been awarded in beauty contest mode Most countries now have adopted market-based approaches such as auctions A spectrum license can be characterized by a tuple: [ f, R, P, Owner_Id, Use_Type, Dur ] f : Frequency R : Region (e.g., local or national) P : Power Owner_Id : License Owner Id Use_Type : Designated Use Dur: License Duration 21

22 Spectrum Engineering: Spectrum Usage Constraints 22

23 EIRP Limit (CCI effect): WLAN Example Frequency Bands Suggested Power (EIRP) GHz Max. (100 mwatt) Indoor GHz Max.(200 mwatt) Indoor GHz (Security, Interior, Military) GHz Max. (200 mwatt) Max. (200 mwatt) Max. (4 watt) Indoor Indoor Outdoor Effective Isotropic Radiated Power (EIRP) = Pout (dbm) Ct (db) + Gt (dbi) the maximum radiated power over all measured angles Pout = transmitter power output (dbm) dbm: 10 log 10 (p in mwatt) Ct = cable attenuation (db) Gt = antenna gain (dbi) dbi: the gain of an antenna system relative to an isotropic radiator (decibels relative to isotropic) 23

24 Spectral Mask (ACI effect) WLAN

25 25 Spectrum Monitoring and Control

26 Spectrum monitoring Spectrum monitoring serves as the eyes and ears of the spectrum management process. The monitoring system provides a method of verification and closes the loop on the spectrum management process: Monitoring supplies information used in determining compliance with rules and regulation, and provides statistical information on the technical and operational nature of spectrum occupancy Monitoring the spectrum should be on a continuous basis (24 hours per day) whether locally, regionally, or globally. 26

27 Spectrum Monitoring

28

29 Spectrum Monitoring Goals The overall goal of spectrum monitoring activities is to support the proper functioning of the general process of spectrum management: Spectrum efficiency in determining planned and actual frequency usage and occupancy, assessing availability of spectrum for future uses. Compliance with national spectrum management regulations to shape and sustain radio environments and user behavior, maximizing the benefit of the spectrum resource to society. Resolution of interference problems for existing and potential users: help users to avoid incompatible frequency usage through identification of sources of harmful interference 29

30 Spectrum Management Software Spectrum management and monitoring systems may contain a software to automate data collection, processing, evaluation, and interference analysis tasks. Using software to save spectrum monitoring results in separate database and correlating this information with the central database of authorized users. 30

31 31 Objectives of Spectrum Management

32 Objectives of Spectrum Management Optimizing usage of the scarce frequency resource. Planning utilization of unused spectrum. Planning the assignment of the frequency spectrum complying with international rules. Eensuring spectrum access for new services and technologies Monitoring the frequency spectrum interference & Minimize radio Frequency Coordination, Registration & Notification. 32

33 Objectives of Spectrum Management Optimizing usage of the scarce frequency resource. Planning utilization of unused spectrum. Planning the assignment of the frequency spectrum complying with international rules. Eensuring spectrum access for new services and technologies Monitoring the frequency spectrum interference & Minimize radio Frequency Coordination, Registration & Notification. 33

34 Spectral Efficiency Data rate: One radio communication system is more "spectrum efficient" than another if it conveys the desired information using less of the spectrum resource 34 spectral efficiency = Rate / Bandwidth (bits/sec/hz) Or spectral efficiency can be expressed as bits/sec/hz/m 2 Occupancy: Spectrum efficiency also involves the arrangement of communication systems within the spectrum resource. In this broader sense, spectrum is used inefficiently when systems are not packed together as tightly as possible in frequency bands (as when excessive guard bands are used), or when portions of frequency bands are unused while other bands with similar physical characteristics are congested.

35 Spectral Efficiency In order to promote spectrum efficiency, spectrum managers must possess some means of: quantifying spectrum use evaluating various radio technologies and frequency selection techniques using the collected data through spectrum monitoring measures of spectrum occupancy and utilization for purposes of making assignments including the effects of spectrum reuse and band clearing efforts 35

36 Spectrum Economics Economic objectives relate to ensuring that spectrum is used in ways which meet the country s goals covering the efficient allocation of resources that spectrum is employed by both private and public sector organizations in ways which meet the country s economic growth and other objectives. 36

37 Spectrum as an Economic Resource 37

38 Economic Dimension Spectrum is an input into the services that end-users (households, firms and public agencies) value Need to maximize the value of outputs produced by the spectrum available Suppose a given quantity of spectrum is available for use in only two sectors, mobile communications and commercial broadcasting. How should it be divided between the two uses? What are the factors? -The value of the services (users point of view: social): S - The economic value of the service: E - The basic amount of spectrum needed: A

39 Spectrum Value Example: Service 1: Mobile (m) Service 2: Broadcasting (b) Total available bandwidth W=20 MHz Service Social value (S) Economic value (E) Basic Amount of spectrum (A) m MHz b MHz How to allocate spectrum to each service given idle situation (no guard bands)?

40 Spectrum Value Example: Service 1: Mobile (m) Service 2: Broadcasting (b) Total available bandwidth W=10 MHz Service Social value (S) Economic value (E) Basic Amount of spectrum (A) m MHz b MHz Case Total value 10 (m) + 10 (m) ( )*2= (m) + 10 * 1(b) ( ) + ( )*10= * 1(b) ( )*20=6

41 Spectrum Pricing Market-based approaches such as auctions and spectrum trading are viewed as superior ways of achieving economic efficiency in assignment than administered methods (e.g., recovering the cost of spectrum management). In practice, auctions tend to be confined to cases where: The spectrum available is in scarce supply; Many firms want to acquire a license; The service to be provided with the spectrum can be precisely defined; The monetary value of the license is relatively high, justifying what can be a complex assignment procedure

42 Common Auction Forms The English Auction: The English auction is the open ascending price auction. In one variant of the English auction, the sale is conducted by an auctioneer who begins by calling out a low price and raises it, typically in small increments, as long as there are at least two interested bidders. The auction stops when there is only one interested bidder. The Dutch Auction: The Dutch auction is the open descending price counterpart of the English auction

43 Common Auction Forms > Single-round sealed-bid auctions: The Sealed-Bid First-Price Auction: In this auction form, bidders submit bids in sealed envelopes; the person submitting the highest bid wins the object and pays what he bid. The Sealed-Bid Second-Price Auction: As its name suggests, once again bidders submit bids in sealed envelopes; the person submitting the highest bid wins the object but pays not what he bid, but the second highest bid. > Multiple-round open auctions > Pure sequential auction: The bidding stops on one license before it begins on the next license > Simultaneous auction: allow for license aggregation