Abstract: A wireless communication system (10) employing quadrature amplitude modulation techniques comprises a system controller (22), at least one radio frequency base transmitter (26), and at least one wireless communication device (35). The system controller (22) generates a downlink call (34) for transmission between the radio frequency base transmitter (26) and the wireless communication device (35). Multiplexing an I-channel bit stream (74) comprised of a first set of calls (70) interleaved together and a Q-channel bit stream (80) comprised of a second set of calls (76) interleaved together generates the downlink call (34). One wireless communication device demultiplexes the downlink call (34) and processes the I-channel bit stream (74). Another wireless communication device demultiplexes the downlink call (34) and processes the Q-channel bit stream (80).

Abstract: A method and apparatus for time-scale modification of speech using a modified version of the Waveform Similarity based Overlap-Add technique (WSOLA) comprises the steps of storing a portion of an input speech signal in a memory, analyzing the portion of the input speech signal to determined at least one filtered pitch value, calculating an estimated pitch value (12) from the at least one filtered pitch value, determining a segment size (14) in response to the estimated pitch value (12), the segment size (14) having a value greater than the estimated pitch value (12), and time-scale compressing (18) the input speech signal in response to the segment size determined.

Abstract: An improved acknowledge-back paging system which returns variable amounts of information requested to the individual or device requesting the information. The system uses a selective call receiver that receives a signal requesting information from the selective call receiver. In response to the signal, multiple acknowledge-back signals comprising the information are transmitted to a receiving station.

Abstract: A selective call receiver includes a receiver (103), a controller (105), and a display (113) for presenting a recovered source document. The receiver (103) provides a received paging message that was generated from the facsimile message of the original source document (208). The received paging message is interpreted and decoded by the controller (105). Using the display (113), a decoded scan line compressed document (1101) is presented in a format that substantially resembles the facsimile message of the original source document (1100).

Abstract: The present invention comprises a method for compressing a plurality of voice signals within a voice communication resource (see FIG. 6) having a given bandwidth within a voice communication system (100). The method comprises the steps of subchanneling the voice communication resource into a plurality of subchannels (441, 442, 443), placing a pair of the plurality of voice signals (401, 402) on a subchannel (441); modulating the pair of the plurality of voice signals (401, 402) about a pilot signal (581) within the subchannel (441) using single sideband modulation; and compressing the time of each of the voice signals (401, 402) within the plurality of subchannels (441, 442, 443), wherein these step provide a compressed voice signal.

Abstract: A communication system (100) providing minimum transmission delay for message delivery to communication transceivers (510) includes a plurality of transmission cells (102, 104) which include one or more receivers (512) and a transmitter (506) and which define geographical transmission areas. The transmitter (506) transmits an address identifying the communication transceiver (510) for which a message is intended and a color code identifying the transmitter (506) during a first scheduled transmission time interval (212). At least one receiver (512) located within the transmission cells (102, 104) receives an acknowledgment including the address and color code generated by the communication transceiver (510) during a second scheduled transmission time interval (216).

Abstract: A modulation scheme (600) useful in a voice paging system in which both of two orthogonal modulation components (500 and 510) are used to carry two halves of a single voice message destined for a receiver, or two separate voice messages for a receiver. The single voice message is transmitted in half the time.