Continuous Phase Modulation of Spectrally Efficient FQPSK Signals
نویسندگان
چکیده
A continuous phase modulation (CPM) implementation alternative of a recently standardized class of Feher-patented quadrature phase-shift keying (FQPSK-B) modulation is proposed. It is based on the fact that FQPSK-B signal has quasi-constant amplitude and continuous phase characteristics, allowing CPM interpretation. Based on this, we derive the modulation index, premodulation filter and alternating change monitor differential encoder for the CPM generated FQPSK-B signal to be fully compatible with original I/Qmodulated one. It is shown that the power spectral density and the bit error rate performance of CPM generated FQPSK-B signal are almost the same as those of I/Q modulated FQPSK-B signal.
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