DIFFERENT OPERATING MODES, SPECTRAL BEHAVIOUR & DATA THROUGHPUT Prepared by: Jack Van der Star, P.Eng. This technical bulletin provides observations of spectrum and data throughput behavior under different bandwidth operating modes, different path conditions and using different (Fast Frame, Packet Bursting, Compression, Dynamic Turbo & WMM) protocol extensions and their combinations. Measurements of simplex and duplex data throughputs were taken over paths in a lab environment and over 10 kilometers using both internal +19 dbi flat panel antenna and external +28dBi parabolic antennas. Using a laboratory link of 5.2 GHz, photos of occupied bandwidth on a spectrum analyzer set to peak hold with link settings of Quarter (5 MHz), Half (10 MHz), Full (20 MHz) and Dynamic Turbo (40 MHz) are shown in Figures 1.0 to 4.0. These illustrate that the occupied bandwidth expands out symmetrically from the centre frequency. An important observation is that the occupied bandwidth remained the same for wireless protocol enhancements individually or in any combination for Fast Frames, Packet Bursting, Compression and WMM. Photos of the 10 kilometer test link, equipment used and rf environment are provided in Figures 5.0 to 9.0 with detailed data throughput test results provided in Tables 1.0 & 2.0 and Figures 10.0 to 67.0. Figure 1.0 Spectrum Using Quarter (5 MHz) Setting with 5.2 GHz Centre Frequency 1
Figure 2.0 Spectrum Using Half (10 MHz) Setting with 5.2 GHz Centre Frequency Figure 3.0 Spectrum Using Full (20 MHz) Setting with 5.2 GHz Centre Frequency 2
Figure 4.0 Spectrum Using Turbo (40 MHz) Setting with 5.2 GHz Centre Frequency Other observations in the use of these bandwidth options are: 1. There is no Dynamic Turbo mode available for the Quarter and Half settings since this is locked or greyed out in the Waveteq GUI. This prevents adjacent spectrum to be grabbed randomly thus improving spectrum management abilities. 2. Dynamic Turbo engages extra spectrum only when data is being transferred over the link. In this mode observations show that the extra 10MHz of spectrum was grabbed on each side of a full (20 MHz) carrier for a total bandwidth of 40MHz. 3. The use of any of the four enhancement modes or their combination of Fast Frames, Packet Bursting, Compression or/and WMM does not occupy any additional adjacent spectrum but does increase throughput more than twice in some cases in the Quarter and Half bandwidth modes. When data throughput approaches 20 Mbps these enhancements provide only marginal improvements. 3
Review of Different Operating Modes or Wireless Enhancements The ShadowMaster and ShadowAP have the following additional modes or wireless enhancements to improve link performance. These must be set the same for both radio interfaces that are used to create a link in order to pass data. Their selection can improve link performance significantly over a plain Wi-Fi interface. An explanation of each wireless enhancement available is described below and results of tests conducted across a laboratory and a 10 kilometer link using both a +19 dbi internal antenna and an external +28 dbi Parabolic Antenna are summarized in Table 1.0 & 2.0. Operating Modes or Wireless Enhancements: 1. Fast Frames: In wireless transmissions there is a lot of extra communication overhead to send each piece of data. Fast Frames will combine many smaller wireless packets to make one 'superpacket' to reduce the overall overhead of a wireless link, thereby improving the efficiency and the speed under certain operating conditions. This feature must be enabled and supported on both sides of the wireless connection in order to work properly. 2. Packet Bursting: Normally a wireless device has to wait for clearance between each transmission. By enabling this, the ShadowMaster will send a 'burst' of up to 3 data packets before waiting the required period. This feature must be enabled and supported on both sides of the wireless connection in order to work properly. 3. Compression: Rather than wasting the valuable bandwidth of the wireless link, the ShadowMaster can utilize compression techniques to reduce the amount of data that needs to be transmitted. This feature must be enabled and supported on both sides of the wireless connection in order to work properly. 4. Dynamic Turbo: Dynamic Turbo Mode utilizes adjacent channels in order to increase data rates. It dynamically adjusts based on the need and the interfering environment. This feature must be enabled and supported on both sides of the wireless connection in order to work properly. 5. WMM: Wi-Fi Multimedia (WMM) is based on the IEEE 802.11e standard. It provides basic quality of service (QoS) features to a Wi-Fi network by prioritizing traffic according to 'voice', 'video', 'best effort', and 'background' categories. WMM does not provide guaranteed throughput, but improves the performance of simple applications that require QoS, such as Wi-Fi Voice over IP (VoIP). Results Summary Results are shown in Table 1.0 for the most sprectrum efficient modes which are provided by selecting the options for Fast Frames, Packet Bursting, Compression and WMM in QUARTER, HALF and FULL Channel width options. WMM provides prioritization for mixed traffic and therefore improves service performance without taking extra frequency spectrum. DYNAMIC TURBO increases throughput (better in non-interfering conditions) by adding adjacent spectrum to do so. Table 1.0 & 2.0 shows the results of selecting individual options and their combinations. Note that the relevant screen images are shown in Figures 10.0 to 67.0 and are referenced in the Tables 1.0 & 2.0. 4
WMM Compression Packet Bursting Fast Frames Technical Bulletin Table 1.0 Data Throughput Results in the LAB and Across a 10 Kilometer Wireless Link Using Internal +19 dbi Panel Antennas and External +28 dbi Parabolic Antenna 1 1 2 2 3 3 TEST 10 Kilometer Link Tests Using +28 dbi Parabolic Antennas 10 Kilometer Link Tests Using +28 dbi Parabolic Antennas 10 Kilometer Link Tests Using +17 dbi Internal Antennas 10 Kilometer Link Tests Using +17 dbi Internal Antennas Lab Tests Using +17 dbi Internal Antennas Lab Tests Using +17 dbi Internal Antennas Data Throughput 5 MHz (Quarter) 10 MHz (Half) 20 MHz (Full) 40 MHz (Dynamic Turbo) Simplex (Kbps) 2995 5858 11479 14372 Duplex (Kbps) 1580 2117 3689 3851 6071 7650 5869 7290 Screen Shot Figures 10.0 & 11.0 14.0 & 15.0 18.0 & 19.0 26.0 & 27.0 x x x Simplex (Kbps) 10572 22008 21562 21914 x x x Duplex (Kbps) 7062 6681 11336 12152 10345 11194 10488 10672 Screen Shot Figures 12.0 & 13.0 16.0 & 17.0 32.0 & 33.0 38.0 & 39.0 Simplex (Kbps) 2941 5699 10634 Duplex (Kbps) 1231 1555 2836 3479 5535 7209 Screen Shot Figures 40 & 41 44 & 45 48 & 49 x x x x Simplex (Kbps) 8408 5993 20540 x x x x Duplex (Kbps) 5835 5379 5531 1574 10392 10419 Screen Shot Figures 42 & 43 46 & 47 50 & 51 Simplex (Kbps) 6636 10781 18573 19493 Duplex (Kbps) 3249 3831 5786 6324 9583 9696 9475 9525 Screen Shot Figures 52 & 53 56 & 57 60 & 61 64 & 65 x x x x Simplex (Kbps) 15689 18911 19599 20170 x x x x Duplex (Kbps) 8295 8824 11200 10730 11092 11164 10790 10779 Screen Shot Figures 54 & 55 58 & 59 62 & 63 66 & 67 NOTE: Data throughput was measured across the link by utilizing a nepim throughput server which is established at one by using putty to enter the radio shell and issuing the command nepim to start the server (ctl C stops it). At the other end of the link (client end), log into the shell and issue the command nepim c [Server IP Address]. This will initiate the data throughput test with the number recorded in the table being the average value. The Duplex test is performed from the client side by issuing the command nepim c [Server IP Address] d 5
WMM Compression Packet Bursting Fast Frames Technical Bulletin Table 2.0 Individual Data Throughput Results Across a 10 Kilometer Wireless Link Using +28 dbi External Parabolic Antennas 1 1a 1b 1c 1d 1e 1f 1g INDIVIDUAL TEST 10 Kilometer Link Tests Using +28 dbi Parabolic Antennas 10 Kilometer Link Tests Using +28 dbi Parabolic Antennas 10 Kilometer Link Tests Using +28 dbi Parabolic Antennas 10 Kilometer Link Tests Using +28 dbi Parabolic Antennas 10 Kilometer Link Tests Using +28 dbi Parabolic Antennas 10 Kilometer Link Tests Using +28 dbi Parabolic Antennas 10 Kilometer Link Tests Using +28 dbi Parabolic Antennas 10 Kilometer Link Tests Using +28 dbi Parabolic Antennas Data Throughput 20 MHz (Full) 40 MHz (Dynamic Turbo) Simplex (Kbps) 11479 14372 Duplex (Kbps) 6871 7650 5869 7290 Screen Shot Figures 18 & 19 26 & 27 x x x x Simplex (Kbps) 20951 20749 x x x x Duplex (Kbps) 10395 10477 10437 10475 Screen Shot Figures 34 & 35 36 & 37 x Simplex (Kbps) 16711 x Duplex (Kbps) 10245 10314 Screen Shot Figures 20 & 21 x Simplex (Kbps) 16843 x Duplex (Kbps) 7585 9978 Screen Shot Figures 22 & 23 x Simplex (Kbps) 14797 x Duplex (Kbps) 9514 9586 Screen Shot Figures 24 & 25 x Simplex (Kbps) 13954 x Duplex (Kbps) 8269 7917 Screen Shot Figures 28 & 29 x x Simplex (Kbps) 21582 x x Duplex (Kbps) 10343 11194 Screen Shot Figures 30 & 31 x x x Simplex (Kbps) 21562 x x x Duplex (Kbps) 10343 11194 Screen Shot Figures 32 & 33 6
10km Link Measurements Using +28 dbi Parabolic Antennas Measurements were undertaken over a 10 km link passing over water and in the presence of co-channel interference at the office end. Figure 5.0 & 6.0 show a spectrum surveys of known SSID s recognized by the receivers at each end of the link which were taken using the ShadowAP s site survey tool. Photos of the installations are also provided of the two communications sites in Figure 7.0 & 8.0. In the photographs please note the ShadowAP and the external 60cm parabolic antennas. End Equipment Configuration (10 km Test Link) Figure 5.0 Spectrum Survey at end showing Co-Channel CH 40 (5200 MHz) interference off the +28 dbi 60 cm Parabolic Antenna as being 4 db down from the ENTEL Test Signal 7
Figure 6.0 Photo of Equipment Installation at the End Showing the 10 Kilometer Path to the Parabolic Antenna at the Side(near end) from the Ski Club Site (far end). ShadowAP Under Test with +19 dbi Internal Antenna +28 dbi 60 cm External Parabolic Antenna 8
Ski Club End Equipment Configuration(10 km Test Link) Figure 7.0 Spectrum Survey at Ski Club end showing Co-Channel interference off the 60 cm +28 dbi Parabolic Antenna with no Interference on CH 52 (5200 MHz) 9
+28 dbi 60 cm Parabolic Antenna ShadowAP Under Test with +19 dbi Internal Antenna Figure 8.0 Equipment Configuration at the Ski Club Site Showing the +28 dbi Antenna, ShadowAP and the 10 Kilometer Path to the Waveteq Site 10
Figure 9.0 10 Kilometer Test Path Over Water from Ski Club Looking Toward the Waveteq Communication Inc. with ShadowAP in Foreground 11
10 Kilometer Data Throughput Tests in the 5 MHz (QUARTER) Mode using +28dBi Parabolic Antennas Figure 10.0 5 MHz (QUARTER) One Way Data Throughput Tests no enhancement option selected using the +28 dbi Parabolic Antenna Figure 11.0 5 MHz (QUARTER) Duplex Data Throughput Tests no enhancement option selected using the +28 dbi Parabolic Antenna 12
Figure 12.0 5 MHz (QUARTER) One Way Data Throughput Tests with Fast Frames, Packet Bursting and Compression options selected using the +28 dbi Parabolic Antenna Figure 13.0 5 MHz (QUARTER) Duplex Data Throughput Tests with Fast Frames, Packet Bursting and Compression options selected using the +28 dbi Parabolic Antenna 13
10 Kilometer Data Throughput Tests in the 10 MHz (HALF) Mode Using +28 dbi Parabolic Antennas Figure 14.0 10 MHz (HALF) One Way Data Throughput Tests no enhancement option selected using the +28 dbi Parabolic Antenna Figure 15.0 10 MHz (HALF) Duplex Data Throughput Tests no enhancement option selected using the +28 dbi Parabolic Antenna 14
Figure 16.0 10 MHz (HALF) One Way Data Throughput Tests with Fast Frames, Packet Bursting and Compression options selected using the +28 dbi Parabolic Antenna Figure 17.0 10 MHz (HALF) Duplex Data Throughput Tests with Fast Frames, Packet Bursting and Compression options selected using the +28 dbi Parabolic Antenna NOTE: This mode selection appears to be one of the most spectrum efficient assuming sufficient link margin is available. 15
10 Kilometer Data Throughput Tests in the 20 MHz (FULL) Mode Using +28 dbi Parabolic Antennas Figure 18.0 20 MHz (FULL) One Way Data Throughput Tests no enhancement option selected using the +28 dbi Parabolic Antenna Figure 19.0 20 MHz (FULL) Duplex Data Throughput Tests no enhancement option selected using the +28 dbi Parabolic Antenna 16
Figure 20.0 20 MHz (FULL) One Way Data Throughput Tests with Fast Frames option selected using the +28 dbi Parabolic Antenna Figure 21.0 20 MHz (FULL) Duplex Data Throughput Tests with Fast Frames option selected using the +28 dbi Parabolic Antenna 17
Figure 22.0 20 MHz (FULL) One Way Data Throughput Tests with Packet Bursting option selected using the +28 dbi Parabolic Antenna Figure 23.0 20 MHz (FULL) Duplex Data Throughput Tests with Packet Bursting option selected using the +28 dbi Parabolic Antenna 18
Figure 24.0 20 MHz (FULL) One Way Data Throughput Tests with Compression option selected using the +28 dbi Parabolic Antenna Figure 25.0 20 MHz (FULL) Duplex Data Throughput Tests with Compression option selected using the +28 dbi Parabolic Antenna 19
Figure 26.0 20 MHz (FULL) One Way Data Throughput Tests with Dynamic Turbo option selected using the +28 dbi Parabolic Antenna Figure 27.0 20 MHz (FULL) Duplex Data Throughput Tests with Dynamic Turbo option selected using the +28 dbi Parabolic Antenna 20
Figure 28.0 20 MHz (FULL) One Way Data Throughput Tests with WMM option selected using the +28 dbi Parabolic Antenna Figure 29.0 20 MHz (FULL) Duplex Data Throughput Tests with WMM option selected using the +28 dbi Parabolic Antenna 21
Figure 30.0 20 MHz (FULL) One Way Data Throughput Tests with Fast Frames and Packet Bursting options selected using the +28 dbi Parabolic Antenna Figure 31.0 20 MHz (FULL) Duplex Data Throughput Tests with Fast Frames and Packet Bursting options selected using the +28 dbi Parabolic Antenna 22
Figure 32.0 20 MHz (FULL) One Way Data Throughput Tests with Fast Frames, Packet Bursting and Compression options selected using the +28 dbi Parabolic Antenna Figure 33.0 20 MHz (FULL) Duplex Data Throughput Tests with Fast Frames, Packet Bursting and Compression options selected using the +28 dbi Parabolic Antenna 23
Figure 34.0 20 MHz (FULL) One Way Data Throughput Tests with Fast Frames, Packet Bursting, Compression and WMM options selected using the +28 dbi Parabolic Antenna Figure 35.0 20 MHz (FULL) Duplex Data Throughput Tests with Fast Frames, Packet Bursting, Compression and WMM options selected using the +28 dbi Parabolic Antenna 24
Figure 36.0 40 MHz (DYNAMIC TURBO) One Way Data Throughput Tests with Fast Frames, Packet Bursting, Compression and WMM options selected using the +28 dbi Parabolic Antenna Figure 37.0 40 MHz (DYNAMIC TURBO) Duplex Data Throughput Tests with Fast Frames, Packet Bursting, Compression and WMM options selected using the +28 dbi Parabolic Antenna 25
Figure 38.0 40 MHz (DYNAMIC TURBO) One Way Data Throughput Tests with Fast Frames, Packet Bursting and Compression options selected using the +28 dbi Parabolic Antenna Figure 39.0 40 MHz (DYNAMIC TURBO) Duplex Data Throughput Tests with Fast Frames, Packet Bursting and Compression options selected using the +28 dbi Parabolic Antenna 26
10 Kilometer Data Throughput Tests in the 5 MHz (QUARTER) Mode using +19dBi Flat Panel Internal ShadowAP Antennas Figure 40.0 5 MHz (QUARTER) One Way Data Throughput Tests no enhancement option selected using the +28 dbi Parabolic Antenna Figure 41.0 5 MHz (QUARTER) Duplex Data Throughput Tests no enhancement option selected using the +28 dbi Parabolic Antenna 27
Figure 42.0 5 MHz (QUARTER) One Way Data Throughput Tests with Fast Frames, Packet Bursting, Compression & WMM options selected using the +19 dbi Internal Antennas. Figure 43.0 5 MHz (QUARTER) Duplex Data Throughput Tests with Fast Frames, Packet Bursting, Compression and WMM options selected using the +19 dbi Internal Antennas. 28
10 Kilometer Data Throughput Tests in the 10 MHz (HALF) Mode Using +19dBi Flat Panel Internal ShadowAP Antennas Figure 44.0 10 MHz (HALF) One Way Data Throughput Tests no enhancement option selected using the +19 dbi Internal ShadowAP Antennas Figure 45.0 10 MHz (HALF) Duplex Data Throughput Tests no enhancement option selected using the +19 dbi Internal ShadowAP Antennas 29
Figure 46.0 10 MHz (HALF) One Way Data Throughput Tests with Fast Frames, Packet Bursting, Compression & WMM options selected using the +19 dbi Internal ShadowAP Antennas Figure 47.0 10 MHz (HALF) Duplex Data Throughput Tests with Fast Frames, Packet Bursting, Compression and WMM options selected using the +19 dbi Internal ShadowAP Antennas 30
10 Kilometer Data Throughput Tests in the 20 MHz (FULL) Mode using +19dBi Flat Panel Internal ShadowAP Figure 48.0 20 MHz (FULL) One Way Data Throughput Tests no enhancement option selected using the +19 dbi Internal ShadowAP Antennas Figure 49.0 20 MHz (FULL) Duplex Data Throughput Tests no enhancement option selected using the +19 dbi Internal ShadowAP Antennas 31
Figure 50.0 20 MHz (FULL) One Way Data Throughput Tests with Fast Frames, Packet Bursting, Compression and WMM options selected using the +19 dbi Internal ShadowAP Antennas Figure 51.0 20 MHz (FULL) Duplex Data Throughput Tests with with Fast Frames, Packet Bursting, Compression and WMM options selected using the +19 dbi Internal ShadowAP Antennas 32
LAB Data Throughput Tests in the 5 MHz (QUARTER) Mode using +19dBi Flat Panel Internal ShadowAP Antennas Desk Bench Figure 52.0 5 MHz (QUARTER) One Way Data Throughput Tests no enhancement option selected using the +19 dbi Internal ShadowAP Antennas Desk Bench Figure 53.0 5 MHz (QUARTER) Duplex Data Throughput Tests no enhancement option selected using the +19 dbi Internal ShadowAP Antennas 33
Desk Bench Figure 54.0 5 MHz (QUARTER) One Way Data Throughput Tests with Fast Frames, Packet Bursting, Compression and WMM options selected using the +19 dbi Internal ShadowAP Antennas Desk Bench Figure 55.0 5 MHz (QUARTER) Duplex Data Throughput Tests with Fast Frames, Packet Bursting, Compression and WMM options selected using the +19 dbi Internal ShadowAP Antennas 34
LAB Data Throughput Tests in the 10 MHz (HALF) Mode Using +19dBi Flat Panel Internal ShadowAP Antennas Desk Bench Figure 56.0 10 MHz (HALF) One Way Data Throughput Tests no enhancement option selected using the +19 dbi Internal ShadowAP Antennas Desk Bench Figure 57.0 10 MHz (HALF) Duplex Data Throughput Tests no enhancement option selected using the +19 dbi Internal ShadowAP Antennas 35
Desk Bench Figure 58.0 10 MHz (HALF) One Way Data Throughput Tests with Fast Frames, Packet Bursting and Compression options selected using the +19 dbi Internal ShadowAP Antennas Desk Bench Figure 59.0 10 MHz (HALF) Duplex Data Throughput Tests with Fast Frames, Packet Bursting and Compression options selected using the +19 dbi Internal ShadowAP Antennas 36
LAB Data Throughput Tests in the 20 MHz (FULL) Mode using +19dBi Flat Panel Internal ShadowAP Desk Bench Figure 60.0 20 MHz (FULL) One Way Data Throughput Tests no enhancement option selected using the +19 dbi Internal ShadowAP Antennas Desk Bench Figure 61.0 20 MHz (FULL) Duplex Data Throughput Tests no enhancement option selected using the +19 dbi Internal ShadowAP Antennas 37
Desk Bench Figure 62.0 20 MHz (FULL) One Way Data Throughput Tests with Fast Frames, Packet Bursting, Compression and WMM options selected using the +19 dbi Internal ShadowAP Antennas Desk Bench Figure 63.0 20 MHz (FULL) Duplex Data Throughput Tests with with Fast Frames, Packet Bursting, Compression and WMM options selected using the +19 dbi Internal ShadowAP Antennas 38
LAB Data Throughput Tests in the Dynamic Turbo Mode using +19dBi Flat Panel Internal ShadowAP Desk Bench Figure 64.0 40 MHz (DYNAMIC TURBO) One Way Data Throughput Tests no enhancement option selected using the +19 dbi Internal ShadowAP Antennas Desk Bench Figure 65.0 40 MHz (DYNAMIC TURBO) Data Throughput Tests no enhancement option selected using the +19 dbi Internal ShadowAP Antennas 39
Desk Bench Figure 66.0 40 MHz (DYNAMIC TURBO) One Way Data Throughput Tests with Fast Frames, Packet Bursting, Compression and WMM options selected using the +19 dbi Internal ShadowAP Antennas Desk Bench Figure 67.0 40 MHz (DYNAMIC TURBO) Data Throughput Tests with with Fast Frames, Packet Bursting, Compression and WMM options selected using the +19 dbi Internal ShadowAP Antennas 40