US Patent 9191043 Direct digital RF conversion

A digital filter bank includes a first sample and hold unit, one or more second sample and hold units one or more quantizers and one or more polyphase component filters. In another aspect, a digital filter bank includes a first sample and hold unit, a discrete time commutator and one or more polyphase component filters. In another aspect, a method for digitally filtering a signal includes sampling an input signal at a first frequency, sampling and holding the first sampled signal at a second frequency, quantizing the one or more second sampled signals to output channelized signals, and filtering the one or more quantized signals and outputting one or more filtered signals using one or more polyphase component filters.