Methods and systems for programmable digital down-conversion

摘要

A radio communication apparatus operable over a wide range of frequencies including a signal processing device is provided. The device performs an analog to digital conversion at a predetermined sample rate independent of a selected frequency band within the wide range of frequencies to generate a digital signal, and digitally processes the digital signal to output a data signal at baseband associated with the selected frequency band.

主权项

1. A radio communication apparatus operable over a wide range of frequencies, comprising:
a signal processing device configured
to receive an analog signal,to perform an analog to digital conversion at a predetermined sample rate independent of a selected frequency band within the wide range of frequencies to generate a digital signal, andto digitally process said digital signal to output a data signal at baseband associated with said selected frequency band, wherein the signal processing device comprises: an analog to digital converter configured to sample the received analog signal at said predetermined sample rate, and to output said digital signal; a quadrature demodulator configured to perform quadrature demodulation of the digital signal, and to output a complex signal including a complex data signal and an image of the complex data signal; a complex channel selection filter configured to receive the complex signal, and to output a filtered complex signal including only one of the complex data signal or the image of the complex data signal; a digital down-sampler configured to receive the filtered complex signal and to generate a down-sampled complex signal that includes one sample out of each group of N sequential samples in the filtered complex signal, where N is an integer number larger than or equal to two and depends on the selected frequency band; and a baseband tuner configured to receive the down-sampled complex signal, and to output a complex baseband data signal.