An analysis filter bank corresponding to a plurality of sub-bands, comprising: multiple sub-filters with different center frequencies which perform multiple complex-type first-order infinite impulse response filtering operations on an audio input signal to generate multiple sub-filter signals; a first set of binomial combiners, each of which performs a weighted-sum operation on a first number of the sub-filter signals with a first set of binomial weights to generate one of multiple sub-band signals; a second set of binomial combiners, each of which performs a weighted-sum operation on a second number of the sub-filter signals with a second set of binomial weights to generate one of multiple lower sub-band-edge signals or one of multiple higher sub-band-edge signals; and multiple envelope detection with decimation devices, which perform multiple envelope detection with decimation operations on the sub-band signals, the lower sub-band-edge signals, and the higher sub-band-edge signals to generate multiple fine spectrums.

An analysis filter bank corresponding to multiple sub-bands, which performs frequency-division filtering on an input signal to generate multiple sub-band signals, the analysis filter bank comprising: a sub-band response pre-compensator which performs a linear filtering on the input signal to generate a response pre-compensated signal, multiple sub-filters with different central frequencies, which perform complex-type first-order infinite impulse response filtering respectively on the response pre-compensated signal to generate multiple sub-filter signals, and multiple binomially-combining and rotating devices based on a set of binomial weights, each of which performs a weighted summation on at least two of the sub-filter signals with the set of binomial weights, and rotates a weighted-summation result with a rotating phase according to a corresponding sub-band central frequency to generate one of the sub-band signals, wherein the at least two of the sub-filter signals are generated by at least two of the sub-filters adjacent in central frequency.

A subchannel detection system for a wireless communication device is disclosed. The system includes an input interface arranged to receive digital data over a predetermined baseband having a plurality of subchannels a plurality of frequency translators arranged to shift the spectrum of the digital data within a subchannel to the center of the baseband, a plurality of low-pass filters arranged to filter frequencies in the middle of the baseband within a subchannel bandwidth, a plurality of correlators arranged to receive a filtered digital signal and correlate the received signal to a subchannel size, and a processing module arranged to receive data from the plurality of correlators and detect one or more active subchannels. The plurality of frequency translators shift the spectrum of all subchannels in the digital data to the center of the baseband; the shifted spectra are filtered by the plurality of low-pass filters and correlated to individual subchannels.

An analysis filter bank corresponding to a plurality of sub-bands, comprising: multiple sub-filters with different center frequencies which perform multiple complex-type first-order infinite impulse response filtering operations on an audio input signal to generate multiple sub-filter signals; a first set of binomial combiners, each of which performs a weighted-sum operation on a first number of the sub-filter signals with a first set of binomial weights to generate one of multiple sub-band signals; a second set of binomial combiners, each of which performs a weighted-sum operation on a second number of the sub-filter signals with a second set of binomial weights to generate one of multiple lower sub-band-edge signals or one of multiple higher sub-band-edge signals; and multiple envelope detection with decimation devices, which perform multiple envelope detection with decimation operations on the sub-band signals, the lower sub-band-edge signals, and the higher sub-band-edge signals to generate multiple fine spectrums.

A subchannel detection system for a wireless communication device is disclosed. The system includes an input interface arranged to receive digital data over a predetermined baseband having a plurality of subchannels a plurality of frequency translators arranged to shift the spectrum of the digital data within a subchannel to the center of the baseband, a plurality of low-pass filters arranged to filter frequencies in the middle of the baseband within a subchannel bandwidth, a plurality of correlators arranged to receive a filtered digital signal and correlate the received signal to a subchannel size, and a processing module arranged to receive data from the plurality of correlators and detect one or more active subchannels. The plurality of frequency translators shift the spectrum of all subchannels in the digital data to the center of the baseband; the shifted spectra are filtered by the plurality of low-pass filters and correlated to individual subchannels.

A method and an apparatus for signal processing: implementing step-by-step orthogonal decomposition of an original signal to be inputted; on the basis of the number of layers of orthogonal decomposition and the edge high frequency bandwidth of the original signal after orthogonal decomposition, generating a finite-length unit impulse response FIR filter; using the FIR filter to filter the edge high-frequency signal of the original signal; and, after passing the signal obtained after filtering and the low frequency signal obtained at each stage of orthogonal decomposition through an orthogonal filter bank, implementing signal synthesis processing.

A method and an apparatus for signal processing: implementing step-by-step orthogonal decomposition of an original signal to be inputted; on the basis of the number of layers of orthogonal decomposition and the edge high frequency bandwidth of the original signal after orthogonal decomposition, generating a finite-length unit impulse response FIR filter; using the FIR filter to filter the edge high-frequency signal of the original signal; and, after passing the signal obtained after filtering and the low frequency signal obtained at each stage of orthogonal decomposition through an orthogonal filter bank, implementing signal synthesis processing.

At a configurable filter bank, commands or command signals are received from an external processing device. The commands or command signals are effective to configure and connect selective ones of the plurality of elements in the filter bank. An acoustic signal is received from a transducer. The acoustic signal is converted to a PDM signal and the PDM signal is converted to a PCM signal.