VE3RTC UHF propagation study

By VE3RGW Mar-2004

R.F.Model 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 802.11B 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:

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.

VE3RTC (UHF site at Don Mill and Finch) • 40’ LDF5 between antenna and duplexer. This contributes a lost of 0.2db on UHF (additional

connector lost 0.1db per junction). • Tx utput power at 12W into duplexer and M500 (HN version) vertical antenna estimated at 12dbi gain. • Rx modeled as general grade receiver (0.5uV at 12db Sinad) with a 10db Rx-front end amplifier (non-

optimized for best noise figure). Estimated best case workable sensitivity as 0.15uv (-124dbm noise floor for hot commercial site profile).

• Duplexer lost estimated at 1db implying a total transmission line lost of 1.5db.• Antenna height estimated as 26x4 = 104m. With site’s altitude at 196m above sea level and

surrounding terrain averaged at 174m considered, HAAT came out as close to 122m. This implies a horizon clearance of 45km (worst case) to 71km(best case).

Test cases configuration

• Initial test model assumes known repeaters as their listed configuration in the previous slide.

• 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.

• Due to difference in calibration, S meter reading can differ between radio. S meter readings are supposed to be verified with calibrated test unit. Most modern hand held (with LCD bar-graph S meter) are calibrated for S9 as full scale. Special precaution or preparation has to be performed before attempt to verify the predicted reading in the last 2 slides of this presentation with a receiver’s S meter. The measuring receiver is expected to be calibrated (S1 for -120dbm level and S9 at -93dbm).

• For normal user, it is recommend to focus on the extreme conditions (workable or not) and the relative profile changes between good and bad cases.

Test points’ relative position

Random fade zone

S9-S6

Over S20

S20-S9

S6-S1

Random fade zone

S9-S6

Over S20

S20-S9

S6-S1

VE3RTC-U estimated transmit coverage (mobile)

Random fade zone

S9-S6

Over S20

S20-S9

S6-S1

Random fade zone

S9-S6

Over S20

S20-S9

S6-S1

VE3RTC-U estimated receive coverage (1W portable)

VE3RTC Key area performance(best case mobile scenery at open area, blue text are field verified reading)

S9+10S879 16 48W, 43 10 34NQEW / Hwy 406St.Catherine

S6S579 51 01W, 43 19 12NQEW / Hwy 403Burlington

S9+20S9+20Ground levelVA3KMJ

S9S879 31 08W, 43 42 59NHwy 401 / Hwy 400GTA west

S9+40S9+2079 07 21W, 43 49 56NSteeles / Brimley (VA3ADM)Scarborough north

S9+20S9+1079 15 05W, 43 44 23NEglington / Brimley (VE3LAU)Scarborough south

S9+10S9+1079 24 36W, 43 45 07NHwy 401/ YongeNorth York

S7S679 25 00W, 43 37 52NLakeshore / JamersonDowntown west

S9+10S979.7009W / 43.44699NQEW / DovalOakville

S9+10S9+1079/58316W / 43.67190NHwy 401 / Hwy 427Airport area

S9S879 30 36W, 43 37 15NQEW / IslingtonEtobicoke

S9+10S9+1079 38 13W, 43 38 59NHwy 401 / DixieMissisauga east

78 37 04W, 43 53 45N

79 20 22W, 43 46 04N

79 25 13W, 44 04 05N

79 21 08W, 43 39 15N

79 17 06W, 43 51 28N

Position

S1

S9+40

S3

S9+10

S9

S4

S9+20

S9+10

Down link

S3

S9+40

S4

S9+10

S9+10

S5

S9+20

S9+10

Up Link

Ground levelVA3CTR

Hwy401/Hwy115Bowmanville

Hwy 401 / DVPGTA core

Hwy 9 / Hwy 404New Market east

Lakeshore / DVPDowntown east

Hwy 7 / McCowan (VE3JKM)Markham

Ground levelVA3XWR

Ground levelVA3MKO

Ref. road junctionLocation

VE3RTC Key area performance(best case portable scenery at open area, blue text are verified reading).

S6S879 16 48W, 43 10 34NQEW / Hwy 406St.Catherine

S2S479 51 01W, 43 19 12NQEW / Hwy 403Burlington

S9+10S9+20Ground levelVA3KMJ

S6S879 31 08W, 43 42 59NHwy 401 / Hwy 400GTA west

S9+10S9+2079 07 21W, 43 49 56NSteeles / Brimley (VA3ADM)Scarborough north

S9+10S9+1079 15 05W, 43 44 23NEglington / Brimley (VE3LAU)Scarborough south

S9S9+1079 24 36W, 43 45 07NHwy 401/ YongeNorth York

S4S579 25 00W, 43 37 52NLakeshore / JamersonDowntown west

S8S979.7009W / 43.44699NQEW / DovalOakville

S9S9+1079/58316W / 43.67190NHwy 401 / Hwy 427Airport area

S9S879 30 36W, 43 37 15NQEW / IslingtonEtobicoke

S9S9+1079 38 13W, 43 38 59NHwy 401 / DixieMissisauga east

78 37 04W, 43 53 45N

79 20 22W, 43 46 04N

79 25 13W, 44 04 05N

79 21 08W, 43 39 15N

79 17 06W, 43 51 28N

Position

S1

S9+40

S2

S9+10

S9

S3

S9+20

S9+10

Down link

No copy

S9+10

S1

S9

S9

S2

S9+20

S9

Up Link

Ground levelVA3CTR

Hwy401/Hwy115Bowmanville

Hwy 401 / DVPGTA core

Hwy 9 / Hwy 404New Market east

Lakeshore / DVPDowntown east

Hwy 7 / McCowan (VE3JKM)Markham

Ground levelVA3XWR

Ground levelVA3MKO

Ref. road junctionLocation