Abstract: A method may include forming a plurality of beams to receive and spatially filter audible sounds from a first microphone and a second microphone. The plurality of beams may include a first unidirectional beam to receive audible sounds from the first microphone and the second microphone, a second unidirectional beam to receive audible sounds from the first microphone and the second microphone, the second unidirectional beam having a spatial null in a direction different from that of the first unidirectional beam, and an omnidirectional beam to receive audible sounds from the first microphone and the second microphone. The method may also include determining a first energy of audible sounds filtered by the first unidirectional beam and a second energy of audible sounds filtered by the second unidirectional beam and, based on the first energy and the second energy, selecting one of the plurality of beams as a selected beam.

Abstract: A method, circuit and article of manufacture for restoring high-frequency content in a first signal includes down-sampling the first signal by a factor to give a second signal; up-sampling the second signal by the same factor to give a third signal; low-pass filtering the third signal to give a fourth signal; high-pass filtering the fourth signal to give a fifth signal; and, adding the fifth signal to the first signal.

Abstract: A method for spatialization using stereo decorrelation. The method generates decorrelated left and right signals by filtering the left input channel using an all-pass filter with a first group delay and filtering the right input channel using an all-pass filter with a second group delay; the second group delay being different than that of the first group delay. The decorrelated left signal is subtracted from the decorrelated right signal to create a second left signal and the decorrelated right signal is subtracted from the decorrelated left signal to create a second right signal. The method generates a side signal by adding the filtered left input channel signal and the filtered right input channel signal. The side signal is added to the second left signal to generate a left output signal the side signal is added to the second right signal to generate a right output signal.

Abstract: An RF receiver (12) includes a channel estimator (52). The channel estimator (52) includes a channel estimation filter (82), error signal generator (84), and normalized Least-Mean-Square (NLMS) filter-definition generator 86. The filter (82), error generator (84) and NLMS filter-definition generator (86) function together as an adaptive estimator. An error signal (90) is formed with a received signal (48). The filter (82) filters an estimated transmit signal (74) constructed from lower confidence decision data (66) and higher confidence known preamble data (30?). An adaptive filter definition (94) is formed in a feedback, loop which minimizes correlation between the estimated transmit signal (74) and the error signal (90). A convergence signal (122) is modulated in synchronism with the changes between lower and higher confidence data in the estimated transmit signal (74).

Abstract: An RF receiver (12) includes a channel estimator (52). The channel estimator (52) includes a channel estimation filter (82), error signal generator (84), and normalized Least-Mean-Square (NLMS) filter-definition generator 36. The filter (82), error generator (84) and NLMS filter-definition generator (86) function together as an adaptive estimator. An error signal (90) is formed with a received signal (48). The filter (82) filters an estimated transmit signal (74) constructed from lower confidence decision data (66) and higher confidence known preamble data (30?). .An adaptive filter definition (94) is formed in a feedback, loop which minimizes correlation between the estimated transmit signal (74) and the error signal (90). A convergence signal (122) is modulated in synchronism with the changes between lower and higher confidence data in the estimated transmit signal (74).