Abstract: A wideband phase detector configured to receive an intermediate frequency (IF) signal having a plurality of information signals at predetermined carrier frequencies and to generate a carrier indication signal used to control one or more attenuators to equalize the signal levels of the information signals thereby enabling a multichannel receiver to process the two information signals in a parallel fashion using a common analog front-end and analog to digital conversion circuit. The circuit may include an attenuation controller configured to provide control signals to the one or more attenuators to attenuate one or more corresponding information signals based on an average of the carrier indication signal.

Abstract: A wideband phase detector configured to receive an intermediate frequency (IF) signal having a plurality of information signals at predetermined carrier frequencies and to generate a carrier indication signal used to control one or more attenuators to equalize the signal levels of the information signals thereby enabling a multichannel receiver to process the two information signals in a parallel fashion using a common analog front-end and analog to digital conversion circuit. The circuit may include an attenuation controller configured to provide control signals to the one or more attenuators to attenuate one or more corresponding information signals based on an average of the carrier indication signal.

Abstract: A channel scanning technique and apparatus provides audio hole suppression in two-way radio communications. Upon detecting the absence of a carrier signal on a priority channel during a priority scan mode of operation, a training waveform is constructed upon returning to the home-channel. The training waveform is applied to audio shaping filters within an audio lineup to suppress transients and minimize or eliminate the occurrence of audio pops at a speaker output thereby reducing the audio hole.

Abstract: A device receives a signal and, prior to demodulating the signal determines whether carrier is present in the received signal based on the correlation depth of the received signal. The device determines a plurality of values for the received signal that indicate the amount of correlation in the received signal and detects the presence of the carrier in the received signal as a function of the plurality of values. The plurality of values can include autocorrelation values and prediction coefficients, wherein the autocorrelation values are estimated based on an autocorrelation function derived for the received signal, and the prediction coefficients are generated using a prediction model that is derived as a function of the autocorrelation values. The prediction coefficients can be summed to generate a decision statistic that is compared to a detection threshold to detect the presence of the carrier.

Abstract: A narrowband communication system (100) includes a base station (102) and a plurality of subscriber units (104). The base station assigns one or more wideband channels to be measured to each subscriber unit (606). The subscriber units tune to their assigned wideband channels and perform narrowband measurements, then report the results to the base station (612). The base station then analyzes the measurement results (614) and selects available wideband channels to be divided into narrowband channels for use by the narrowband system.

Abstract: A channel scanning technique and apparatus provides audio hole suppression in two-way radio communications. Upon detecting the absence of a carrier signal on a priority channel during a priority scan mode of operation, a training waveform is constructed upon returning to the home-channel. The training waveform is applied to audio shaping filters within an audio lineup to suppress transients and minimize or eliminate the occurrence of audio pops at a speaker output thereby reducing the audio hole.

Abstract: A narrowband communication system (100) includes a base station (102) and a plurality of subscriber units (104). The base station assigns one or more wideband channels to be measured to each subscriber unit (606). The subscriber units tune to their assigned wideband channels and perform narrowband measurements, then report the results to the base station (612). The base station then analyzes the measurement results (614) and selects available wideband channels to be divided into narrowband channels for use by the narrowband system.

Abstract: A device receives a signal and, prior to demodulating the signal determines whether carrier is present in the received signal based on the correlation depth of the received signal. The device determines a plurality of values for the received signal that indicate the amount of correlation in the received signal and detects the presence of the carrier in the received signal as a function of the plurality of values. The plurality of values can include autocorrelation values and prediction coefficients, wherein the autocorrelation values are estimated based on an autocorrelation function derived for the received signal, and the prediction coefficients are generated using a prediction model that is derived as a function of the autocorrelation values. The prediction coefficients can be summed to generate a decision statistic that is compared to a detection threshold to detect the presence of the carrier.