Abstract: A mobile communication device (100) includes a vocoder (104) for vocoding speech (500) received at the mobile communication device. The parameters output by the vocoder are used to generate a voicing quality metric (208). The voicing quality metric is used to provide feedback to the user of the mobile communication device by various feedback modalities including visual (114), audible (108), and tactile modalities (118) to indicate when the user should speak louder to overcome ambient noise. The voicing quality metric is also used by other communications equipment (304, 312) to decide if communication activity is needed.

Abstract: An apparatus (213) and corresponding methods (FIG. 7) to facilitate maintaining crypto synchronization while processing communication signals in a communication unit includes a vocoder (215) configured to convert input audio band signals to vocoder output frames; a crypto processor (217) configured to encrypt the vocoder output frames to provide encrypted output frames; and a synchronizer (219) configured to substitute in a predetermined manner synchronization information corresponding to an encryption state of the crypto processor for a portion of the encrypted data in a portion of the encrypted output frames to provide resultant output synchronization frames suitable for synchronizing a decryption process at a target communication unit.

Abstract: An apparatus (213) and corresponding methods (FIG. 7) to facilitate maintaining crypto synchronization while processing communication signals in a communication unit includes a vocoder (215) configured to convert input audio band signals to vocoder output frames; a crypto processor (217) configured to encrypt the vocoder output frames to provide encrypted output frames; and a synchronizer (219) configured to substitute in a predetermined manner synchronization information corresponding to an encryption state of the crypto processor for a portion of the encrypted data in a portion of the encrypted output frames to provide resultant output synchronization frames suitable for synchronizing a decryption process at a target communication unit.

Abstract: A communication unit (101) and corresponding methods are arranged and constructed to detect acknowledgment messages as an Originator or respond with an acknowledgment message as a Target on a time division channel. The communication unit includes a transceiver (201) configured to support air interfaces (113, 115) with other communication (103, 105) units according to frequency hopping patterns and a controller (203) cooperatively controlling the transceiver to, for example, send a call setup message identifying a target communication unit and a pseudo-random frequency hopping pattern; and to determine whether an acknowledgment message from the target communication unit is present in a signal received according to the pseudo-random frequency hopping pattern.

Abstract: An apparatus (213) and corresponding methods (FIG. 7) to facilitate maintaining crypto synchronization while processing communication signals in a communication unit includes a vocoder (215) configured to convert input audio band signals to vocoder output frames; a crypto processor (217) configured to encrypt the vocoder output frames to provide encrypted output frames; and a synchronizer (219) configured to substitute in a predetermined manner synchronization information corresponding to an encryption state of the crypto processor for a portion of the encrypted data in a portion of the encrypted output frames to provide resultant output synchronization frames suitable for synchronizing a decryption process at a target communication unit.

Abstract: A method (60 or 70) and system of reducing collisions in an asynchronous communication system can include the steps at a transmitter (200) of generating (61) a set of known preamble waveforms and transmitting (64) at least one distinguishable preamble waveform based on an association with a call type and a receiver identifier. The method (70) can also include the steps at a receiver (300) of receiving (71) at least one preamble waveform among a set of different preamble waveforms which toggle between two symbol frequencies, the different preamble waveforms being distinguishable by at least having one among a different symbol frequency spacing and a different symbol toggling duty cycle. The method further includes the step of selecting (73) to decode a preamble waveform based on at least one among the different symbol frequency spacing and the different symbol toggling duty cycle.

Abstract: A system, wireless device (402) and method receive a set of soft metrics (614) associated with a block of symbols during a predetermined time interval, use the set of soft metrics (614) to form an initial interference power estimate, form a moving-average estimate of interference power (616) corresponding to each predetermined time interval, and scale the set of soft metrics (614) according to the corresponding interference power estimate resulting in a set of scaled metrics (618). Then they limit the dynamic range of the set of scaled metrics (618), linearly quantize the limited metrics, and output the linearly quantized limited metrics (628) to a memory buffer. The size of the memory buffer containing the linearly quantized limited metrics (628) is smaller than the size of a memory buffer required to store the received soft metrics (614). The linearly quantized limited metrics (628) are then used as input to a decoder.