| Summary: | Radio Spectrum is finite entity and its demand is increasing day by day. One of such crowded spectrums is the spectrum allocated (licensed) to Professional Mobile Users (PMU). PMU are using Analogue Communication utilizing Frequency Modulation (FM) with 25 KHZ channel spacing. With increase in demand in spectrum, FCC has reduced channel spacing to 12.5KHZ and demanded to use Digital Communication. With reduction in in channel spacing, there is reduction in deviation in carrier frequency. This change suggests to use less bandwidth for speech. The speech bandwidth is reduced by 70%. Such a grand reduction is possible through speech compression techniques. As compared to analogue speech compression, digital speech compression is efficient and hence it is used. Such requirements put total signal processing in digital domain. There are many standards laid for such demand by different organizations in the world according to different technology. This paper focus on ETSI standard used in Asia and European countries for Digital Mobile Radio. It suggests possible change in Modulation and Channel Encoding method for improving Power and Bandwidth measurements. We also tested these results under worst signal measurement conditions. Result shows that with use of methods suggested by us has four times Bandwidth efficient, less complex and equal power efficient as compared to existing system. The proposed schemes seems to be an important finding in measurement and sensing systems.
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