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View Full Version : Question UMTS 900 OR GSM 900 has a better coverage



white_Noise
2012-01-13, 06:16 AM
Which is better is terms of coverage? UMTS 900 or GSM 900 ? In terms of the Idle mode coverage I believe it's the GSM since it has a higher "BCCH" power, but in the dedicated mode the power of the radio for both is the same "40 W" whereas the UE sensitivity is much higher for UMTS handsets, so I'm a bit confused here on which to judge.

venom
2012-01-13, 01:59 PM
Here you're talking about the same spectrum with different technologies.
DL Coverage would remain similar (not much different) if you're using the same power of the radio module. Please note that coverage or losses is dependent on Frequency/Spectrum.

I am sure you're familiar with the formula

http://upload.wikimedia.org/wikipedia/en/math/a/1/0/a100432cfbaa6417ffccfab51609f53b.png

If wavelength and frequency are same then the phase speed would also remain same in both technologies.

firstmaxim
2012-01-13, 02:05 PM
Which is better is terms of coverage? UMTS 900 or GSM 900 ? In terms of the Idle mode coverage I believe it's the GSM since it has a higher "BCCH" power, but in the dedicated mode the power of the radio for both is the same "40 W" whereas the UE sensitivity is much higher for UMTS handsets, so I'm a bit confused here on which to judge.

900 MHz band exhibits the same propagation characteristics irrespective of technology. The definition of coverage is not complete, unless you consider the receiver's sensitivity. Then, receiver sensitivity is a function of the service offered. Unlike GSM, LTE offers diverse services, which necessitate different coverage definitions.

white_Noise
2012-01-13, 02:58 PM
900 MHz band exhibits the same propagation characteristics irrespective of technology. The definition of coverage is not complete, unless you consider the receiver's sensitivity. Then, receiver sensitivity is a function of the service offered. Unlike GSM, LTE offers diverse services, which necessitate different coverage definitions. Agree, but for a cell equipped with both technologies, same band, the UMTS coverage will be better since the UE sensitivity is much higher
in UMTS..correct? but for the Idle mode, the BCCH power is usually ten times the PCPICH power, in that case which will be serving better?

dmitry28
2012-01-13, 03:05 PM
UMTS has better coverage
see post http://www.finetopix.com/showthread.php?21638-WCDMA-Refarming-in-900-MHz

white_Noise
2012-01-13, 04:05 PM
UMTS has better coverage
see post http://www.finetopix.com/showthread.php?21638-WCDMA-Refarming-in-900-MHz nice paper, but it mentions nothing about the UE sensitivity.

aubidamax
2012-01-13, 04:38 PM
hi

23702
23703

thanks............

Philippe
2012-01-13, 05:10 PM
Generally link budgets are limited by the uplink coverage. If you compare an uplink link budget, taking into account better sensitivity of UMTS but lower UE transmit power (21dBm for voice UMTS, 24dBm for data UMTS, 33dBm for GSM 900) and higher interference margin for UMTS, you will find that UMTS 900 link budget is slightly better for voice than GSM 900 voice and around same performances for UMTS 900 PS 64kbps UL and GSM 900 voice.

white_Noise
2012-01-13, 05:12 PM
hi

23702
23703

thanks............ Sorry buddy, but I'm asking about UMTS900

white_Noise
2012-01-13, 05:15 PM
Generally link budgets are limited by the uplink coverage. If you compare an uplink link budget, taking into account better sensitivity of UMTS but lower UE transmit power (21dBm for voice UMTS, 24dBm for data UMTS, 33dBm for GSM 900) and higher interference margin for UMTS, you will find that UMTS 900 link budget is slightly better for voice than GSM 900 voice and around same performances for UMTS 900 PS 64kbps UL and GSM 900 voice. thanks a lot, seems like a logical approach that gets to the point.

firstmaxim
2012-01-13, 06:42 PM
Agree, but for a cell equipped with both technologies, same band, the UMTS coverage will be better since the UE sensitivity is much higher
in UMTS..correct? but for the Idle mode, the BCCH power is usually ten times the PCPICH power, in that case which will be serving better?

If you are considering the CPICH coverage in UMTS, you need to account for the processing gain. CPICH has a SF =256 and the corresponding processing gain at the UE is 24 dB.