Abstract: A wireless communication system is configured for adaptive modulation of a transmitted symbol. The specific modulation and/or coding is uniquely identified and data related thereto is embedded within the transmitted symbol. A receiver extracts pilot signals form the transmitted symbol and performs a correlation analysis to identify the particular modulation/coding used for that particular transmitted symbol. This permits adaptive modulation on a symbol-by-symbol basis. A base station communicating with a plurality of peripheral subscribers may utilize different modulation/coding for each subscriber depending on channel conditions.

Abstract: A fixed wireless access system generally comprises a consumer premise equipment (CPE) unit, that is connected via an Ethernet interface to a personal computer or local area network, and a base station unit that is connected via an Ethernet interface to a network. As such, the CPE unit is preferably easily user-installed while the base station unit is preferably tower-mounted within a 1-5 mile range of the CPE unit. Both the CPE unit and base station unit preferably incorporate an integrated data transceiver/switch that enables a radio frequency air link operating in the 2.5-2.686 GHz range. Orthogonal frequency division multiplexing is used in the uplink and downlink transmissions between CPE units and base station units.

Abstract: A fixed wireless access system generally comprises a consumer premise equipment (CPE) unit, that is connected via an Ethernet interface to a personal computer or local area network, and a base station unit that is connected via an Ethernet interface to a network. As such, the CPE unit is preferably easily user-installed while the base station unit is preferably tower-mounted within a 1-5 mile range of the CPE unit. Both the CPE unit and base station unit preferably incorporate an integrated data transceiver/switch that enables a radio frequency air link operating in the 2.5-2.686 GHz range. Orthogonal frequency division multiplexing is used in the uplink and downlink transmissions between CPE units and base station units.

Abstract: A system for channel assignment in a trunked transmission communication system including a plurality of subscribers. A plurality of subscribers is provided home channel assignment to reduce collisions. A home channel alias is provided for home channel coverage where a designated home channel is unavailable. A system for call grouping is provided to avoid talk group splitting. A first check is used to determine if other channels are conducting communications with identical home and talk group information. A second check is available after a temporary channel assignment. In one system both the home channel aliasing and call grouping are performed.

Abstract: A system for channel assignment in a trunked transmission communication system including a plurality of subscribers. A plurality of subscribers is provided home channel assignment to reduce collisions. A home channel alias is provided for home channel coverage where a designated home channel is unavailable. A system for call grouping is provided to avoid talk group splitting. A first check is used to determine if other channels are conducting communications with identical home and talk group information. A second check is available after a temporary channel assignment. In one system both the home channel aliasing and call grouping are performed.

Abstract: A trunked radio repeater communication system capable of use in a networked system includes a plurality of distributive switches and a unique signaling protocol and a switching protocol for interconnecting the trunked transmission communications systems into a wide area network that provides an expanded feature set of radio communications capabilities. The trunked radio repeater system including a protocol supporting communications for repeaters and/or subscribers conducting communications using existing protocols, such as the Logic Trunked Radio (LTR) protocol and supporting additional special functions.

Abstract: A trunked radio repeater communication system capable of use in a networked system includes a plurality of distributive switches and a unique signaling protocol and a switching protocol for interconnecting the trunked transmission communications systems into a wide area network that provides an expanded feature set of radio communications capabilities. The trunked radio repeater system including a protocol supporting communications for repeaters and/or subscribers conducting communications using existing protocols, such as the Logic Trunked Radio (LTR) protocol and supporting additional special functions.

Abstract: A high speed data interface unit that is fully compatible with existing, trunked, land mobile voice transceivers is provided. Data rates of up to 4800 baud using bilevel modulation are achievable without the use of dedicated data transceivers, or the designation of a dedicated data channel. The data interface includes a microprocessor based modem having data pulse formation, data recovery, and pulse filtering circuits that optimize available channel bandwidth for communication of digital data.

Abstract: A unique data recovery circuit which is able to recover transmitted digital data with a data clock embedded therein. No initial timing signals are required for operation of the data recovery circuit. Instead the data clock is recovered from the received data and used to synchronize the flow of data through the circuit. Noise pulses and other anomalous transients are rejected by the circuit so that the data output accurately corresponds to the data transmitted. Operation of the invention is achieved through a number of expedients which include a random access memory delay line which delays interpretation of the data until the data clock has been recovered. A uniquely integrated delay switching network is utilized to switch recovery of the clock from the received data to the delayed data. A phase locked loop and an integrate, sample and dump circuit are also employed, both of which use asynchronous ripple counters to achieve the primary objective of the invention which is to recover the data transmitted.

Abstract: An improved automatic/remote RF instrument monitoring system including a plurality of transponders configured to operate with one of a plurality of parameter sensing instruments remotely located from an interrogate/receiver. The interrogate/receiver transmits RF transponder activation signals in the form of a tone modulated onto a carrier. In response to the activation signals, the transponders "wake-up" and transmit an RF transponder signal which is received and processed by the interrogate/receiver. The transponders include a transmission enable circuit which initiates transmission of the RF transponder signals at random times after receipt of the activation signals. The RF transponder signals are formed by a plurality of spaced transponder information packets.

Abstract: A radio frequency transponder is provided that combines high signal sensitivity in the receive mode and variable frequency capability in the transmit mode in a low component and power efficient design. A single tuned amplifier acts as the externally quenched oscillator of a superregenerative receiver when the transponder is operated in the receive mode, and as the carrier frequency generator when the transponder is operated in the transmit mode.

Abstract: A frequency detector completely implemented with digital logic circuitry is disclosed. The frequency detector hereof employs a unique phase locked loop digitally implemented with asynchronous ripple counters, and a digitally implemented amplitude comparator and signal integrator. The detector is especially adapted for implementation in CMOS hardware, or similar hardware having low current drain characteristics. The selectivity of the detector can be set to a narrow bandwidth for excellent noise discrimination characteristics.