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A symbol stream contains alternate QPSK and 16-QAM symbols. If symbols ...


A symbol stream contains alternate QPSK and 16-QAM symbols. If symbols from this stream are transmitted at the rate of 1 mega-symbols per second, the raw (uncoded) data rate is _______ mega-bits per second (rounded off to one decimal place).  

Answer: 

Since alternative QPSK and 16-QAM used, data rate of uncoded data is (2+4)/2 = 3 Mbps

Number of bits in one QPSK symbol is 2 and

number of bits in one 16-QAM symbol is 4

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