Motorola Corporation

David R Petreye

Stephen H Dunkerton

David F Willard

Robert D Fennell

Gary D Erickson

Gary R Reynolds

Daniel A Morera

Scott G Chapman

Robert J Schwendeman

Clinton C Powell, Ii

Lu Chang

Jian-Cheng Huang

James Michael Keba

Chun-Ye Susan Chang

Barbara Diaz Laflin

Lorenzo Ponce De Leon

Marcus A Gade

A communication device (400) with a polarization diversity antenna configuration, having a first antenna (410) with a first plane of polarization and a second antenna (412) with a second plane of polarization. Signal strength of a demodulated signal when the antenna switch (420) is coupled to one of the antennas (410, 412) is measured by a signal strength measuring circuit (440) to generate a short-term average signal power (SA) representing signal strength over a first predetermined number of symbol periods, a medium-term average signal power (MA) representing signal strength over a second predetermined number of symbol periods, and a long-term average signal power (LA) representing signal strength over a third predetermined number of symbol periods, greater than the second predetermined number of symbol periods and first predetermined number of symbol periods. Switching between antennas (410, 412) is made in response to differences between SA, MA and LA.

Communication device having antenna switch diversity, and method therefor

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).

Method and apparatus for dynamic group calling in a selective call system

A data communication receiver (106) is assigned for receiving message signals within one or more message transmission frames (FIG. 3) transmitted in a predetermined sequence. The message signals include address (1604) and message (1608) information, and information (1710) designating one or more additional message transmission frames to which the data communication receiver (106) is responsive for receiving the message signals. The data communication receiver (106) includes a receiver (804) for receiving the message signals, a decoder (830, 816), coupled to the receiver (804), for decoding the address (1604) and designating (1608) information received during the assigned transmission frames, and a memory (850), for storing the message information received which is intended for the data communication receiver (106) during the assigned transmission frames. The decoder (830, 816) is further responsive to the designating (1608) information, for decoding additional address (1604) information received during the one or more additional transmission frames designated by the designating (1608) information, and the memory (850) further stores the message information associated therewith which is received during the one or more additional transmission frames. A display (842) is used to display the stored message information.

Data communication receiver having variable length message carry-on

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).

Addressing method for conserving power in distributed information

A method for tracking a received signal comprises the steps of setting (635) a counter (130) to a first value indicative of a first signal voltage, determining a center threshold of the received signal, and determining a number of center transitions of the received signal within a predetermined time period. The method further comprises the step of automatically decrementing (685, 695) the counter (130) to a second value indicative of a second signal voltage in response to expiration of a predetermined amount of time, wherein the second value differs from the first value by a predetermined amount determined by the number of center transitions of the received signal within the predetermined time period.

Method and apparatus for digitally tracking highs and lows of a signal

A selective call terminal receives selective call information from a message originator. A transmission time is scheduled for the selective call message by a selective call system controller. A plurality of simulcast schedulers coupled to the controller receive and store the selective call message and the transmission time. The simulcast schedulers have an equalization time stored therein, the equalization times for each of the simulcast schedulers calculated by the system controller using simulcast receivers for measuring signal time differences between transmitters. The simulcast schedulers provide the selective call message to corresponding transmitters at a time to transmit the selective call message, the time determined by the transmission time and the equalization time. Transmitter settings and code types defining signalling protocol, data bit rate, carrier frequency and transmitter power, for each message are varied in accordance with information received from the system controller. Each simulcast scheduler can also function as a selective call terminal for a local selective call system.

Simulcast scheduler

A selective call receiver (106) receives a radio frequency signal having digital signals contained within symbols. The signal demodulated by the receiver (804) comprises a substantially constant DC offset voltage and an AC voltage (1810) indicative of the information contained within the symbols. A threshold level extraction circuit (808) which extracts the offset voltage is synchronously controlled (1840) providing for sampling of the received signal by the threshold level extraction circuit in substantially the center of each symbol.

Synchronized offset extraction in a data receiver

A paging station remote control system decoder is described. The paging system decoder is responsive to signals generated in accordance to a signalling scheme comprising a series of tones and timed pauses generated by a paging system encoder. The paging system decoder then causes a paging transmitter station to key in an analog or binary modulation mode or to switch from one mode to another without first dekeying the paging transmitter.

Paging universal remote control decoder

A paging station remote control system capable of providing analog or binary modulation modes is described. Control of the paging base station is effected through a signalling scheme comprising a combination of tones and timed pauses generated in response to control signals supplied either manually or by a paging terminal. The paging system is capable of transitions between binary and analog modulation modes without first dekeying the paging transmitter.

Paging universal remote control system

A paging station remote control system encoder is described. The paging system encoder generates signals in accordance with a predetermined signalling scheme comprising a series of tones and timed pauses and generated in response to control signals supplied either manually or by a paging terminal. The paging system encoder provides control signals which instruct a paging transmitter station to key in the analog or binary modulation mode or to switch from one mode to another without first dekeying the paging transmitter.

Growing community of inventors

Lake Worth, FL, United States of America

David R Petreye