A phase interpolation receiver for receiving angle modulated radio frequency
signals.
The receiver comprises mixers for down-converting the received angle modulated
signal to lower frequency signals, limiters, interpolation filters, and a demodulator.
The mixers down-convert the received RF signal to a low IF intermediate frequency
signal. The low IF intermediate frequency signal is limited. After further down-conversion
to zero IF, using quadrature mixers, the limited signal is phase interpolated.
The intermediate frequency is chosen such that the limited signal comprises an
unwanted signal at twice the intermediate frequency that acts as a noise spreading
signal for spectrally spreading of quantization noise generated by the limiters,
and the cut-off frequency of the interpolation filters is chosen such that the
unwanted signal and the spread quantization noise are suppressed.
