Cellular radio systems questions

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In cellular radio systems, the concept of bits per cycle is clarified as spectral efficiency, typically measured in bits per second per Hertz of bandwidth. For narrowband FM systems, an approximate technique to determine necessary frequency deviation is often based on the modulation index. The noise figure of a low noise amplifier can be found on its datasheet, and it is essential to understand the relationship between noise metrics and noise figure. A specific example discussed involves a 1200Hz analog signal encoded with 8-level PCM, resulting in a bit rate of 6600 bits per second over a defined bandwidth. Understanding these parameters is crucial for effective cellular radio system design.
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With regards to cellular radio systems1. how many bits of information does each cycle of a sinewave carry on a minimum channel?

modulator characteristics
2. A system has narrowband fm characteristics.. name me a rule which is an approximate technique to find the necessary freqeuncy deviation?

3 What formulae gives the noise figure of a low noise amplifier?
 
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Mickydawg25 said:
With regards to cellular radio system top level design1. how many bits of information does each cycle of a sinewave carry on a minimum channel?

modulator characteristics
2. A system has narrowband fm characteristics.. name me a rule which is an approximate technique to find the necessary freqeuncy deviation?

3 What formulae gives the noise figure of a low noise amplifier?

1. Bits per cycle does not make any sense. Bits/s per Hz of bandwidth is a typical metric for spectral efficiency.

2. A low noise amplifier will have noise figure on its datasheet. Do you have some other noise metric such as nV/sqrt(Hz), that you are trying to convert to NF?
 
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In the case of single carrier modulation you could say that a spectral efficiency of 1b/s per Hz is equivalent to 1 bit per carrier cycle. Is this what you were looking for?
 
OK this is the system

1200Hz analogue signal encoded using 8 level PCM
This spec results in a bit rate of 6600 bit/s
Signal transmitted over 1100m, 1200Hz bandwidth, FM carrier.
Carrier freq is 875000000Hz.
Allowed 1W carrier Pt and Pr.
antennas - omnidirectional.
antenna feeders=low loss, max 0.1 dB atten.

On a min. bandwidth channel each cycle of each sinewave carries how many bits of
information?

In order to define the modulator characteristics, FM modulator freq dev is computed.
System has narrowband FM characteristics so that the necessary frequency deviation can be obtained by an approximate technique such as what?
 

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