Abstract: A selective call device (106) for monitoring at least two communication systems. The selective call device (106) has a receiver (204) for receiving information from a first communication system (110), a processor (206) for referencing a time slot assignment on the first communication system (110) to a common time base. The processor (206) calculates timing information relating a common time base and a transmitter (222) transmits the timing information to the second communication system (120) informing the second communication system (120) when to transmit information to the selective call device (106) with reference to the common time base.

Abstract: A technique is used in a simulcast radio communication system (200) for providing improved local time information. The technique includes, in a fixed portion (300) of the simulcast radio communication system (200), alternatively transmitting in a radio signal a first local time and a second local time in a predetermined protocol position that occurs periodically in a signaling protocol, wherein the first local time and second local time differ by a time zone interval. A radio (500) that receives the radio signal presents local time to a user in manner that indicates the first and second local times.

Abstract: A message transmission system (100) and method for providing flexible roaming to a receiving device (126) which includes a code memory (422) which stores addresses of a first type (1202) to enable reception of messages within a local geographic area, and an address of a second type (1214) to enable reception of the messages within a different geographic area. The message transmission system (100) includes a transmitter (SSID1) which transmits the addresses of the first type with the messages associated therewith within the local geographic area, and a controller (204) which controls conversion of the addresses of the first type to the address of the second type, and transfer of the address of the second type with the messages associated with the addresses of the first type to a transmitter (SSID2-SSID5) which transmits the address of the second type with the messages associated therewith to the receiving device when operating within the different geographic area.

Abstract: A selective call system provides dynamic group calling by transmitting a paging message (FIG. 10) to each data communication receiver in a defined group. The paging message comprises a group call address (1040) and frame (1050) and phase (1060) information identifying when the group message will be transmitted. The group call message is then transmitted (326, 328) in the assigned frame and phase. When the paging messages comprising the group call address are received (1904) by the data communication receivers, the group call address is decoded and temporarily stored (1910) as an address of the receiver. Within the identified frame and phase, address correlation with the group call address is attempted (1918, 1926) and the group call message, when found (1920), is received and decoded (1922) as a paging message. After reception of the group call message, the group call address and associated stored information is erased (1924).

Abstract: A messaging system capable of transmitting messages to receivers which roam between coverage areas. In one configuration, a coverage area (100) is divided into a plurality of zones (110). A single simulcast system identification (SSID) number is assigned which consists of a local identification number which identifies the coverage area (100), a zone identifier which identifies a zone (110) within the coverage area, traffic splitting flags and a frequency. For larger roaming areas, a network (200) is defined as consisting of a plurality of service areas (210) and is identified by network roaming identification information (NRI). NRI information and/or SSID information is stored in a receiver according to desired coverage and like information is transmitted in the corresponding zone or service area.

Abstract: Network roaming information (NRI), which comprises identifies a network (200) and a service area (210) within the network (200), a receiver address, is transmitted in a network (200) during a predetermined number of time slots of a signal, whereby the signal is transmitted in consecutive cycles, each cycle comprising a plurality of consecutive time slots. The placement of the NRI in the transmitted signal is made to be predicted by a receiver so that the receiver can compute an expected time slot location of a NRI to be compared with a stored NRI. The placement of the NRI is made according to an algebraic relationship between moduloN of the transmission frequency of the signal, moduloN of the order of the cycle, and moduloN of a portion of the NRI, wherein N is an integer.

Abstract: A messaging system and method capable of transmitting group messages throughout a Network (200) such that receivers which are outside of a "local" or "home" area of coverage receive such group messages, whereas receivers which are in a "local" area of coverage over ride and do not receive the group message as a result of decoding system identifiers and ignoring those messages having network roaming identification.

Abstract: A selective call receiver (111) receives a synchronous selective call signal (99) having synchronization portions (102 and 104) and a frame identification portion (106). Upon finding the signal the selective call receiver's bit and frame synchronizers (126 and 128) synchronize to a frame (100) of the signal and a frame ID decoder (130) decodes the frame ID (106). A comparator (136) compares the received frame ID (106) with an ID (142) assigned to the receiver, and optionally a first and second mask (134A and 134B) to determine the number of frames until an occurrence of a desired frame and conserves power until the occurrence of the desired frame (188).

Abstract: A time diversity communication system (150) comprises a messaging terminal (154), a queue (156) at the messaging terminal for queuing incoming messages, an encoder (158) for encoding a first fragment of a message and the remaining fragments of a message, a transmitter (160) for repeatedly transmitting the first fragment in a plurality of time slots to at least one selective call receiver (201) operating in a first mode, the number of time slots equaling a desired number of repeat transmissions and wherein the first fragment contains instructions for decoding the remaining fragments in a second mode by the selective call receiver, the transmitter (160) also repeatedly transmits the remaining portions of the message in subsequent time slots and at least one selective call receiver that decodes the first fragment and remaining fragments of the message in accordance with instructions in the decoded first fragment.

Abstract: A communication receiver (106) receives an address code word (1800) of a transmitted message, the message comprising the address code word (1800) and an associated data portion (1610), the address code word comprising an address portion (1802,1804). The communication receiver (106) corrects (2104) up to a predetermined number of bit errors in the received address code word (1800). The communication receiver (106) can conserve power following a failed correction of the address code word (1800). Alternatively, the communication receiver (106) compares (2108,2111) the address portion (1802,1804) of the corrected address code word (1800) to at least one predetermined subscription address (1704,1706). The communication receiver (106) can conserve power following a determination of no match (2110,2114,2308) between the address portion (1802,1804) of the corrected address code word (1800) and the at least one predetermined subscription address (1704,1706).

Abstract: A method of locating a portable communication unit (108) having a transmitter (852) for transmitting acknowledge back signals, consists of the steps of transmitting, to the portable communication unit (108) from the communication cell transmitters (104), an information signal which consists of a predetermined color code word which identifies a subset of the communication cells (500) for which radio coverage does not overlap; receiving an acknowledge back signal from the portable communication unit (108) consisting of a reported color code value determined from the color code word transmitted in the information signal; and analyzing the reported color code value to determine a cell location of the portable communication unit (108).

Abstract: A paging receiver device and method are disclosed in which analog information transmitted from an external source such as a paging transmitter are received and decoded. The analog information includes at least one voice message. The voice message is recovered, digitized, and stored in one of a plurality of message slots in a memory of the paging receiver. In response to a paging user's request, the digitized stored message is recalled from memory, reconverted from digital information to analog information, and used to produce audible voice information being a replica of the original analog voice message.

Abstract: A selective call receiver receives a signal having a baud rate and comprising a number of phases. The number of phases are time division multiplexed to form the signal. The selective call receiver has selective call address information assigned thereto and includes a receiver for receiving and demodulating the signal and a memory for storing predetermined information. A demultiplexer is coupled to the receiver and the memory for demultiplexing the signal to recover one of the number of phases in response to the predetermined information and the baud rate. The selective call receiver also includes a decoder coupled to the demultiplexing means for decoding said one of said number of phases of said signal to derive a selective call message therefrom.

Abstract: A selective call receiver (111) has a first mask (134A) stored within the selective call receiver (111) indicative of a first period of reception for receiving a transmitted communication signal (99) having a plurality of packets (100). Each of the transmitted packet (100) has message information (110). An identifier (106) identifies the packet (100). The control signal (108) is representative of a second mask (134B) indicative of a second period of reception. The second mask is compared with the first mask for determining the second period of reception of the selective call receiver (111). A correspondence between the first and second masks determines whether to change the first period of reception of the selective call receiver (111) for receiving at least one additional packet.

Abstract: A selective call receiver (106) receives one or more message packets of a transmitted fragmented message, where each of the one or more message packets includes an address (1605) and message data (1610), and the message data (1610) includes an indication (1702) of whether more message packets are to be received for the fragmented message. The selective call receiver (106) receives an address of each message packet, and then correlates (2908) the address to one or more predetermined addresses. After a successful correlation (2908), the selective call receiver (106) decodes the message data (1610) of each message packet, and then successively stores (2928, 2936, 2942) the decoded message data (1610) to reconstruct the fragmented message. The selective call receiver (106) determines that the fragmented message is completely reconstructed after detection (2918) in the decoded message data (1610) an indication (1702) that no more message packets are to be received for the fragmented message.

Abstract: In a battery powered selective call receiver receiving a synchronous signal, a battery saving method extends battery life by optimizing the amount of time the receiver circuit is activated when searching for the signal after previously acquiring synchronization. The battery saving method allows for turning the selective call receiver on without activating the receiver circuit. The receiver circuit is activated at a time later than the energization of the selective call receiver, where the time of activation of the receiver circuit is determined in response to the time passed since synchronization was last acquired and the system signal stability.

Abstract: A symbol synchronizer for a communication receiver receiving multi-level data signals includes a reference clock generator for generating a reference clock signal having a predetermined time period, a state change detector for detecting state changes occurring within the received multi-level data signals over the predetermined time period to enable determining a time location corresponding to the detected state change wherein the time locations are assigned predetermined numeric values corresponding to the time locations determined, an accumulator for accumulating a time location for the time locations selected, and a phase adjusting circuit which is responsive to the time location count for adjusting the phase of the reference clock signal relative to the received multi-level data signal.

Abstract: A transmitter system for transmitting coded message signals on a plurality of channels of which at least one channel to be assigned to each of a plurality of geographical areas. The coded message signals include channel identification information and message information being transmitted in a sequence of coded transmission slots on each of the plurality of channels. The sequence of coded transmission slots are transmitted offset in time such that a particular transmission slot is not substantially simultaneously transmitted on any of the plurality of channels.A receiver capable of receiving the coded message signals during a predetermined coded transmission slot being transmitted on the plurality of channels is also described.

Abstract: A signalling protocol comprising a plurality of interleaved phases is transmitted at various baud rates, the various baud rates being multiples of a base baud rate. The signalling protocol allows a selective call receiver to decode at an operating baud rate equivalent to the base baud rate irrespective of the transmission baud rate by decoding only a portion of the transmitted signal, the portion decoded determined by the baud rate and the address of the selective call receiver.

Abstract: A paging receiver receives a message signal having an address field and a data field. The message has at least one address within the address field and a plurality of packets in the data field. The data packets contain a predetermined amount of information. A method for conserving power during reception of a message signal having an address field comprising a number of addresses involves entering the power conserving mode of operation after attempting to correlate a predetermined number of addresses with the paging receiver's address, where the predetermined number is less than the number of addresses in the address field. In addition, message information may be included within a plurality of packets by several methods including placing a corresponding plurality of addresses in the address field, each address indicating the occurrence of message information, or by indicating in one packet that information follows in a subsequent packet.