Toronto Cantonese Trunk repeaters VA3CTR network propagation study. By VE3RGW Feb-2004

Transcription

1 Toronto Cantonese Trunk repeaters VA3CTR network propagation study By VE3RGW Feb-2004

2 R.F.Model configuration The study is performed with Radio Mobile software. Terrain model is derived based on NASA s SRTM 3 arc sec data. The initiating parameter for the test model is derived based on last known system information and future planned configuration. This test is to identify possible coverage from a list of selected sites and see if a solution can be derived so as to improve voice quality of Chinese ham repeater network within GTA.. The hope is to find a group of stations that can provide the largest combined footprint but minimum overlap. Target linking will be build via internet but possibility of building private B point to point link is also considered. An assumed factor of 50% city attenuation profile are employed on all test cases. This factor is subject to future calibration based on field test data. The following slides show system configuration and predicted UHF coverage of selected VE3 sites and potential C/I clearance between controlled co-channel application. In order to help future field verification of this predicted result, all link test case will be worked upon mobile user. The later portion of this presentation will focus on their combined effect and cross influence. The selected sites are: Site VA3CTR VA3XWR VE3RTC VA3KMJ VA3TIF Address 115 Silver Rose Cres.Markham 2726 Castelbreidge Drive, Missisauga Shepperd / Kennedy, Scarborough 103 EDENBRIDGE DRIVE 94 Crestwood Rd, Thornhill. Position W / N W / N W / N W / N W / N

3 VA3CTR between antenna and duplexer. This contributes a lost of 1.4db on UHF (additional connector lost 0.1db per junction). VA3CTR output power at 15W into duplexer and a Diamond X500 or equivalent collinear vertical antenna at 11.5dbi gain. Average noise floor -114dbm implying a usable system sensitivity of 0.5uV(/12db SINAD) for general grade receiver. Duplexer lost estimated at 1.2db implying a total transmission line lost of 2.8db. Roof altitude at 12m. UHF antenna ground clearance as 13m. With site s altitude at 201m above sea level but surrounding terrain averaged at 223m considered, HAAT fell into -10m range. This implies a horizon clearance of 14km to 60km (best case scenery). VA3XWR 25 FSJ4 between antenna and first junction between ground junction and duplexer. This contributes a lost of =1.1db on UHF (additional connector lost 0.1db per junction). VA3XWR output power at 15W into duplexer and a Diamond X50 or equivalent vertical antenna at 7.2dbi gain. Average noise floor -114dbm implying a usable system sensitivity of 0.5uV(/12db SINAD) for general grade receiver. Duplexer lost estimated at 1.2db implying a total transmission line lost of 2.5db. Roof altitude at 12m. UHF antenna ground clearance as 13m. With site s altitude at 180m above sea level and surrounding terrain averaged at 170m. HAAT is a clean 21.4m and implies a clean horizon clearance of 19 to 56km (best case scenery). VA3KMJ between antenna and equipment. This contributes a lost of 1.4db on UHF (additional connector lost 0.1db per junction). VA3KMJ output power estimated at 15W directly into a Diamond X50 or equivalent vertical antenna at 7.2dbi gain. Average noise floor -114dbm implying a usable system sensitivity of 0.5uV(/12db SINAD) for general grade receiver. Simplex profile do not need to consider duplexer system lost. Roof altitude at 12m. UHF antenna ground clearance as 13m. With site s altitude at 180m above sea level and surrounding terrain averaged at 170m. HAAT is a clean 21.4m and implies a clean horizon clearance of 19 to 56km (best case scenery).

4 VE3RTC (UHF at temporary location) between antenna and duplexer. This contributes a lost of 0.3db on UHF (additional connector lost 0.1db per junction). VA3TIF output power at 35W into duplexer and an unknown collinear vertical antenna estimated at 10dbi gain. But with installation profile at the south facing balcony, the system acts like a 180 degree corner reflect antenna (azimuth 200TN). Average noise floor -114dbm implying a usable system sensitivity of 0.3uV(/12db SINAD) for general grade receiver. Duplexer lost estimated at 0.8db implying a total transmission line lost of 1.2db. Antenna height estimated as 20x4 = 80m. With site s altitude at 196m above sea level and surrounding terrain averaged at 159m considered, HAAT came out as close to 92m. This implies a horizon clearance of 39.5km to 65km (best case scenery). VA3TIF between antenna and duplexer. This contributes a lost of 1.4db on UHF (additional connector lost 0.1db per junction). VA3TIF output power at 15W into duplexer and a Diamond X50 or equivalent collinear vertical antenna at 7.2dbi gain. Average noise floor -114dbm implying a usable system sensitivity of 0.5uV(/12db SINAD) for general grade receiver. Duplexer lost estimated at 0.8db implying a total transmission line lost of 2.4db. If simplex profile employed, system lost will improve to 1.6db. Roof altitude at 12m. UHF antenna ground clearance as 13m. With site s altitude at 196m above sea level and surrounding terrain averaged at 190m considered, HAAT came out as close to 19m. This implies a horizon clearance of 18km to 60km (best case scenery).

5 Test cases configuration Initial test model assumes known repeaters as their listed configuration in the previous slide. Search area (future built) repeaters default to 15W output, double section 5/8 wavelength vertical collinear and 12m antenna height (roof level) above site s ground level. Receiver s sensitivity estimated at 0.25uV/12db SINAD. A site running with a different UHF profile will be placed in between footprint of two co-channel macro site. This site is to provide an intermediate support to the network so that user can switch to an alternate frequency to get around area with poor C/I performance on the macro frequency ( MHz +5MHz offset). If test frequency MHz is not applicable, we can consider to use MHz simplex on a third CTCSS tone (besides 103.5Hz and 88.5Hz) Or we can use UHF link frequency for VE3RTC (if it is still available). This practice is to minimize possible interference to the macro repeaters reception while no interference will be caused by the macro system for users in these buffer zone. To minimize C/I impact, transmit footprint of these intermediate system should be designed to face away from any macro sites prime coverage also. Mobile users will be stated as a known road junction or known sites. Default configuration will be 15W output, quarter wavelength ground plane antenna on roof of vehicle. Receiver s sensitivity estimated at 0.25uV/12db SINAD and free from off band cross modulation interference. Portable users in the test model are assumed to be 1W output rubber ducky antenna profile with receiver sensitivity at around 0.2uV/12db SINAD.

6 Test points relative position

7 VA3CTR estimated coverage Over S1 Random fade zone Serious fading can occur 5km from site due to terrain blockage (HAAT at -10m)

8 VA3CTR Key area performance (best case scenery at open area). Location Ref. road junction Position Down link Up Link VA3CTR VA3MKO +20 VA3KMJ S7 VE3RTC VA3XWR Markham Hwy 7 / McCowan (VE3JKM) W, N Scarborough north Steeles / Brimley (VA3ADM) W, N Scarborough south Eglington / Brimley (VE3LAU) W, N North York Hwy 401/ Yonge W, N Downtown east Lakeshore / DVP W, N S1 Downtown west Lakeshore / Jamerson W, N New Market east Hwy 9 / Hwy W, N S1 GTA core Hwy 401 / DVP W, N GTA west Hwy 401 / Hwy W, N Airpot area Hwy 401 / Hwy /58316W / N Etobicoke QEW / Islington W, N Missisauga east Hwy 401 / Dixie W, N Missisauga core Hwy 403 / Hwy W, N Oakville QEW / Doval W / N Burlington QEW / Hwy W, N St.Catherine QEW / Hwy W, N S1

9 VA3MKO (VA3TIF) estimated coverage Over S1 Random fade zone

10 VA3MKO Key area performance (best case scenery at open area). Location Ref. road junction Position Down link Up Link VA3CTR VA3MKO VA3KMJ VE3RTC VA3XWR S1 Markham Hwy 7 / McCowan (VE3JKM) W, N Scarborough north Steeles / Brimley (VA3ADM) W, N Scarborough south Eglington / Brimley (VE3LAU) W, N North York Hwy 401/ Yonge W, N Downtown east Lakeshore / DVP W, N Downtown west Lakeshore / Jamerson W, N New Market east Hwy 9 / Hwy W, N GTA core Hwy 401 / DVP W, N GTA west Hwy 401 / Hwy W, N Airpot area Hwy 401 / Hwy /58316W / N S7 Etobicoke QEW / Islington W, N Missisauga east Hwy 401 / Dixie W, N Missisauga core Hwy 403 / Hwy W, N Oakville QEW / Doval W / N Burlington QEW / Hwy W, N St.Catherine QEW / Hwy W, N

11 VA3KMJ estimated coverage (1/4 wavelength GP) Over S1 Random fade zone

12 VA3KMJ Key area performance (best case scenery at open area). Location Ref. road junction Position Down link Up Link VA3CTR VA3MKO VA3KMJ VE3RTC VA3XWR Markham Hwy 7 / McCowan (VE3JKM) W, N Scarborough north Steeles / Brimley (VA3ADM) W, N Scarborough south Eglington / Brimley (VE3LAU) W, N North York Hwy 401/ Yonge W, N Downtown east Lakeshore / DVP W, N Downtown west Lakeshore / Jamerson W, N New Market east Hwy 9 / Hwy W, N GTA core Hwy 401 / DVP W, N GTA west Hwy 401 / Hwy W, N Airpot area Hwy 401 / Hwy /58316W / N Etobicoke QEW / Islington W, N Missisauga east Hwy 401 / Dixie W, N Missisauga core Hwy 403 / Hwy W, N Oakville QEW / Doval W / N S1 S1 Burlington QEW / Hwy W, N St.Catherine QEW / Hwy W, N

13 VE3RTC(VE3HIT) estimated coverage

14 VE3RTC Key area performance (best case scenery at open area). Location Ref. road junction Position Down link Up Link VA3CTR Invalid at backside of blockage +20 VA3MKO Invalid at backside of blockage +20 VA3KMJ VE3RTC (VE3HIT) VA3XWR Markham Hwy 7 / McCowan (VE3JKM) Invalid 06W, 43 at 51 backside 28N of blockage +20 Scarborough north Steeles / Brimley (VA3ADM) Invalid 21W, 43 at 49 backside 56N of blockage Scarborough south Eglington / Brimley (VE3LAU) W, N North York Hwy 401/ Yonge W, N Downtown east Lakeshore / DVP W, N Downtown west Lakeshore / Jamerson W, N S7 New Market east Hwy 9 / Hwy W, Invalid at backside 05N of blockage GTA core Hwy 401 / DVP W, N GTA west Hwy 401 / Hwy W, N Airpot area Hwy 401 / Hwy /58316W / N Etobicoke QEW / Islington W, N Missisauga east Hwy 401 / Dixie W, N Missisauga core Hwy 403 / Hwy W, N Oakville QEW / Doval W / N Burlington QEW / Hwy W, N S7 St.Catherine QEW / Hwy W, N

15 VA3XWR estimated coverage Over S1 Random fade zone

16 VA3XWR Key area performance (best case scenery at open area). Location Ref. road junction Position Down link Up Link VA3CTR VA3MKO VA3KMJ VE3RTC S1 S1 VA3XWR Markham Hwy 7 / McCowan (VE3JKM) W, N Scarborough north Steeles / Brimley (VA3ADM) W, N Scarborough south Eglington / Brimley (VE3LAU) W, N North York Hwy 401/ Yonge W, N Downtown east Lakeshore / DVP W, N Downtown west Lakeshore / Jamerson W, N New Market east Hwy 9 / Hwy W, N GTA core Hwy 401 / DVP W, N S7 GTA west Hwy 401 / Hwy W, N S1 Airpot area Hwy 401 / Hwy /58316W / N Etobicoke QEW / Islington W, N S7 Missisauga east Hwy 401 / Dixie W, N S7 Missisauga core Hwy 403 / Hwy W, N Oakville QEW / Doval W / N Burlington QEW / Hwy W, N St.Catherine QEW / Hwy W, N S7

17 Deploying a GTA echolink repeaters network Voice will suffer seriously when C/I between a host system and the co-channel interfering system is lower then 10db (ideal case for commercial systems calls for over 17db C/I). Multiple interference test case are performed to identify the best option where a lowest C/I case can be achieved with the current available sites. We can lower our standard to 12db C/I. This enables a larger usable area for co-channel system although slight warbling will be felt at the borders of a system. The plan employs two sets of repeater frequencies shared among systems. Under most cases, UHF channel MHz will be used to support close range portables and mobiles within 25km range. When signal from UHF system has degraded to the extent on failing or suffering serious co-channel interference, user is expect to switch over to the alternate channel. The scheme below described how this alternate channel can be provided. Easiest default option is to use VE3FLF gateway via VE3RTC s VHF system on MHz. Or we can consider using VE3RTC (UHF) if it can be modified to use echolink (this can be done if secure internet link is available at VE3HIT s site. One option besides using standard high speed internet is to set up B low speed link between VE3FLF and VE3HIT). If we can obtain clearance to use a second UHF repeater channel, we can consider deploy sites between VA3CTR and VA3XWR to close up the gap in order to support unbroken UHF service within the combined footprint. VA3MKO or VA3KMJ are both good candidates to support this option. If second UHF repeater channel is not available but we insist to provide non-break UHF coverage. We can consider to run simplex link at VA3MKO or VA3KMJ. This is an option that a reasonable degree of degradation at macro s sites uplink receive is expected. But the impact can be minimized if the prime control area of each site can be classified clearly while users will use minimal access power at all possible cost. Or we can use other simplex UHF frequency for these buffer area if such frequency is available. The best configuration identified as having VA3CTR and VA3XWR as two macro system. VA3CTR shall cover Markham, N.Scarborough, Stouville, Aurora. VA3XWR shall cover Oakville, Missisauga, South Brampton, Etobicoke, airport and part of the western down town area. VA3KMJ shall cover Vaugn, Thornhill, Richmond Hill, North York and North Etobicoke. In order to provide improve coverage to shadow zone at Eglington/Weston, we can use YAGI antenna at VA3KMJ to focus its coverage to SW (200TN azimuth) while retaining a high rejection towards VA3CTR. VE3RTC VHF channel will be a wide area macro system to cover eastern sectors all the way to Oshawa.

18 VA3CTR,VA3XWR co-channel interference study 1 Slight warble but usable coverage This plot shows C/I ratio between VA3CTR and VA3XWR (both on omni antenna). This test case assumes a user of VA3CTR being jammed by VA3XWR. Red zones are the area where voice readability will suffer. We can see most prime area like Markham, Scarborough with clear CI status.

19 VA3CTR,VA3XWR co-channel interference study 2 Slight warble but usable coverage This plot shows C/I ratio between VA3CTR and VA3XWR (both on omni antenna). This test case assumes a user of VA3XWR being jammed by VA3CTR. Red zones are the area where voice readability will suffer. We can see most prime area like Missisauga and S.Etobicoke with clear CI status.

20 VA3KMJ on 6 element Yagi 200TN azimuth This plot shows how we can use VA3KMJ with a Yagi to provide coverage to the high C/I zone between VA3CTR and VA3XWR. This is a controlled footprint focus on using restricted coverage public test frequency inside a coordinated repeater channel zone for VA3CTR.

21 coverage of the combined network VA3CTR+VA3TIF+VA3XWR Too much overlap in Markham and Scarborough not easy to fallback if simplex MHz has to be used. Advantage of more channel capacity at core service area if different contact groups has to be served at the same time. VA3CTR prime coverage MHz 103.5Hz VA3TIF prime coverage MHz 103.5Hz VA3XWR prime coverage MHz 88.5Hz Marginal coverage at Etobicoke, network still suffer poor service between Keele-Hwy427.

22 coverage of the combined network VA3CTR+VA3KMJ+VA3XWR Less interlap between VA3CTR and VA3KMJ. Less issue if we must launch network with MHz simplex at buffer zone. VA3CTR prime coverage MHz 103.5Hz VA3KMJ prime coverage MHz 103.5Hz VA3XWR prime coverage MHz 88.5Hz Solid coverage at Etobicoke, Network supports no-break coverage between Scarborough and Missisauga.

23 2.4GHz intra WiFi LAN The idea of using WLAN here is to support a 10Mbps digital LAN where key users participating in this project can be joined via VOIP applications. Model indicates part of the sites in this study can be joined with enhanced B devices (using 24db gain dish antenna and mW output). This option is critical if we are planning to enable echolink support on VE3RTC while the future commercial site or the temporary alternate site (VE3HIT) do not have high speed internet access. The first study is performed between the temporary site of VE3RTC (VE3HIT) with the nearest possible donor site VE3FLF. The two sites are in direct visible range less then 1km. Directional antenna is to be used so as to maximize rejection to potential interference or intrusion. The test case is built on using 20-24db gain dish antenna on both sides and power from the PCI network card directly (no amplifier required). The test case shows a chance to get 3-4 S point above the minimum level to grant full 10Mbps.