GSM Network Coverage I

We already calculated Link budget in previous post so we retain how to calculate coverage in GSM network.
Type Cell in GSM  
1/ Okumara-Hata model 
The Okumara-Hata model is the most commonly used model for macro-cell coverage planning. It is used for the frequency ranges 150-1000 MHz and 1500-2000 MHz and this model depends on two variables Antenna height and frequency. It is applied with GSM for macro cell in three location type: Typical Urban, Typical Suburban and rural. The range of calculation is from 1 to 20 km. The loss between the transmitting and receiving stations is given as:

1.1 Typical Urban  
Path loss = 69.55 + 26.16logf_c + (44.9 – 6.55logh_b) logd – 13.82logh_b – a(h_m)(dB)  
where is
- fc  the frequency (MHz), 
- hb is the BTS antenna height (m),
- hm is the mobile antenna height (m)
- a(h_m) is a function of the MS antenna height, 
- d is the distance between the BS and MS (km), and 
- a(h_m)match to size of city and given by:
For Small and medium-sized cities 
a(h_m) = [1.1log(f_c) – 0.7]h_m – [1.56log(f_c) – 0.8] 
For large cities 
a(h_m) = 8.29[log(1.54h_m)]² – 11  fc smaller than 200MHz
a(h_m) = 3.2[log(11.75h_m)]² – 4.97 fc bigger than 400Mhz

1.2 Typical Suburban 
Path loss = Path loss (Urban) – 2[9log(f_c/28)²) – 5.4] (dB)  
1.3 Rural
 Path loss = Path loss (Urban) – 4.78(logf_c)²+ 18.33logf_c – 40.94 (dB)  
 Character of position that we install Base Station

-         Antenna Type: APX906515L-T0-0

-          Antenna height: 26m

-          Region: urban and suburban

-          Feeder Type: HFC22D(A)LS Cable 2006

-          Feeder loss: 3.71dB per 100m

-          Feeder length: 46m

-       Allowable Path loss (uplink) 142.66dB 

-       Allowable Path loss (downlink) 141.97dB (Allowable pathloss please see previous post)

 we will perform for 

150 ≤ f_c ≤ 2200 MHz

30 ≤ h_b ≤ 200 m

1 ≤ h_m ≤ 10 m

1 ≤ d ≤20 Km

 we study case Urban
Path loss = 69.55 + 26.16logf_c + (44.9 – 6.55logh_b) logd – 13.82logh_b– a(h_m)(dB) 
I determine that the region is small.  
a(h_m) = [1.1log(f_c) – 0.7]h_m – [1.56log(f_c) – 0.8] 
h_m=1.5m
fc =900MHz 
a(h_m) = [1.1*log(900)-0.7]*1.5 - [1.56*log(900)-0.8]= 0.016dB

Base Station Coverage 
- Mobile transmitting distance (MS)
Logd = [Path loss - (69.55+26.16*logf_c) + 13.82*logh_b + a(h_m)] / (44.9 - 6.55*logh_b)  
Allowable Path loss (Uplink) = 142.66 dB 
Logd    = [142.66 - (69.55+26.16log900) + 13.82log26 + 0.016] / (44.9 – 6.55log26)  = 0.4454
So Distance for mobile transmitting d(MS) = 2.78km
- Base Station  transmitting distance (BS) 
Allowable Path loss (downlink) 141.97dB 
Logd    = [141.97 - (69.55+26.16log900) + 13.82log26 + 0.016] / (44.9 – 6.55log26) = 0.6240
So Distance for Base Station transmitting d(BS) = 2.66km
 Can see related post Link Budget of Base Station Subsystem calculation I and Link Budget of Base Station Subsystem calculation II and GSM Network Coverage II