Abstract: A spatial diversity system for digital mobile telephone networks which comprises at least two antennas, one antenna being part of a primary (or master) unit and the other being part of a diversity (or slave) unit, each unit having processing means to detect the "quality" of digital audio signals received by their respective antennas, the "quality" comprising link quality, AGC level and parity errors; the primary unit being capable of comparing the "quality" of the audio signals received by each antenna, selecting the higher "quality" signal and transmitting the higher "quality" signal to the telephone network.

Abstract: A digital wireless subscriber telephone unit for wireless connection with a base station. The subscriber unit has a baseband processor which is coupled to storage means for the baseband functions. The baseband processor is direct access coupled to a modem processor whereby the two processors may communicate with each other. The modem processor generally acts as the master in the system, although lock-out means may be used in certain circumstances. The signal from the modem processor is converted to an analog signal, which is subjected to deglitching, and the deglitched signal is then upconverted and filtered to form an IF signal which is thereafter amplified. The amplified IF signal is combined with a signal generated by a synthesizer to provide an RF signal. On the basis of certain signals received from the base station, the baseband processor produces initiating signals which determines whether the subscriber unit will be in the transmit mode or the receive mode.

Abstract: A band pass-band reject filter in which the filter housing which comprises the resonant cavity is contained within an annular wall that is supported at each end by an end plate. The filter is connected to an instrument rack or the like by the distal ends of bolts which extend between the end plates and which lie closely along side the annular wall. The end plates are soldered to the annular housing. The bolt heads are soldered to the end plate and their shafts are soldered to the side wall.

Abstract: A wireless digital telephone system containing at least one emulated base station plus one or more subscriber stations, the emulated base station comprising a station similar to the subscriber station but having the capability of initiating a synchronization process whereby it is enabled to assign time slots to the subscriber station within the frame pattern of an amplitude signal by means of monitoring for positive edges in the signal.

Abstract: A system for the wireless transmission of multiple information signals utilizing digital time division circuits between a base station and a plurality of subscriber stations. The subscriber stations may be fixed or movable. The number of time division circuits is determined by the transmission quality of the signals. The base station is interconnected with an external information network, which may be analog and/or digital. The information signals are selected from the group consisting of voice, data, facsimile, video, computer and instrumentation signals. The modulation level of the signals and the power applied to the system are adjusted in accordance with signal error detection in the system. The system is provided with spatial diversity by using a plurality of antennas selectively spaced from each other to provide relatively high signal reception despite signal fading. The base station operates over a plurality of RF channel pairs.

Abstract: A digital wireless subscriber telephone unit for wireless connection with a base station. The subscriber unit has a baseband processor which is coupled to storage device for the baseband functions. The baseband processor is direct access coupled to a modem processor whereby the two processors may communicate with each other. The modem processor generally acts as the master in the system, although lock-out circuit may be used in certain circumstances. The signal from the modem processor is converted to an analog signal, which is subjected to deglitching, and the deglitched signal is then upconverted and filtered to form an IF signal which is thereafter amplified. The amplified IF signal is combined with a signal generated by a synthesizer to provide an RF signal. On the basis of certain signals received from the base station, the baseband processor produces initiating signals which determine whether the subscriber unit will be in the transmit mode or the receive mode.

Abstract: A digital wireless subscriber telephone unit for wireless connection with a base station. The subscriber unit has a baseband processor which is coupled to storage device for the baseband functions. The baseband processor is direct access coupled to a modem processor whereby the two processors may communicate with each other. The modem processor generally acts as the master in the system, although lock-out circuit may be used in certain circumstances. The signal from the modem processor is converted to an analog signal, which is subjected to deglitching, and the deglitched signal is then upconverted and filtered to form an IF signal which is thereafter amplified. The amplified IF signal is combined with a signal generated by a synthesizer to provide an RF signal. On the basis of certain signals received from the base station, the baseband processor produces initiating signals which determine whether the subscriber unit will be in the transmit mode or the receive mode.

Abstract: In a broadcast telephone system for communicating information signals over an assigned frequency channel, the combination of a synthesizer for generating a signal at the assigned frequency and a PROM storing a plurality of sets of first and second signals associated with different predetermined assignable frequencies.

Abstract: A digital wireless subscriber telephone unit for wireless connection with a base station. The subscriber unit has baseband processor which is coupled to storage means for the baseband functions. The baseband processor is direct access coupled to a modem processor whereby the two processors may communicate with each other. The modem processor generally acts as the master in the system, although lock-out means may be used in certain circumstances. The signal from the modem processor is converted to an analog signal, which is subjected to deglitching, and the deglitched signal is then upconverted and filtered to form an IF signal which is thereafter amplified. The amplified IF signal is combined with a signal generated by a synthesizer to provide an RF signal. On the basis of certain signals received from the base station, the baseband processor produces initiating signals which determine whether the subscriber unit will be in the transmit mode or the receive mode.

Abstract: A system for the wireless transmission of multiple information signals utilizing digital time division circuits between a base station and a plurality of subscriber stations. The subscriber stations may be fixed or movable. The number of time division circuits is determined by the transmission quality of the signals. The base station is interconnected with an external information network, which may be analog and/or digital. The information signals are selected from the group consisting of voice, data, facsimile, video, computer and instrumentation signals. The modulation level of the signals and the power applied to the system are adjusted in accordance with signal error detection in the system. The system is provided with spatial diversity by using a plurality of antennas selectively spaced from each other to provide relatively high signal reception despite signal fading. The base station operates over a plurality of RF channel pairs.

Abstract: A subscriber communication system includes a base station in a network with a plurality of subscriber stations, wherein control information is communicated between the base station and the subscriber stations over a radio control channel (RCC) at a frequency selected by the base station from a plurality of predetermined frequencies. The a base station transmits control messages including a unique network number over the RCC. Each subscriber station processes the network number in the control message received over the RCC to enable the subscriber station to process the control message in accordance with whether the subscriber station is in the same network as the base station. The timing of communications transmitted by a subscriber station over a given communication channel between a base station and the subscriber station is refined upon initial establishment of the communication channel.

Abstract: In a communication system that comprises a plurality of subscriber stations in RF communication with a base station having multiple sequentially repetitive time slots, each time slot being assigned to a particular subscriber station, means to change either the frequency or the time slot configurations, or both, in the event of a deterioration of transmission quality caused by modulation change, frequency channel interference, equipment failure, or the like, or by the entrance of additional subscriber stations going on line.

Abstract: In a broadcast telephone system for communicating information signals over an assigned frequency channel, the combination of a synthesizer for generating a signal at the assigned frequency and a PROM storing a plurality of sets of first and second signals associated with different predetermined assignable frequencies.

Abstract: A base station in a subscriber communication network for communicating signals between subscriber stations and an external communication network having a plurality of ports. The base station includes a communication circuit for enabling simultaneous communications between a plurality of the ports and a plurality of subscriber stations over a given communication channel having multiple sequentially repetitive time slots; a remote-connection processor for directing communications between the time slot assigned to a given subscriber station and a given external communication network port; and an exchange for connecting the communication circuit to the external communication network ports.

Abstract: A base station for use in a subscriber communication network for communicating signals between subscriber stations and an external communication network having a plurality of ports includes a communication circuit for enabling simultaneous communications between a plurality of the ports and a plurality of the subscriber stations over a given communication channel having multiple sequentially repetitive time slots; an exchange for connecting the communication circuit to the external communication network ports; and a remote-connection processor coupled to the communication circuit by the exchange and by a base-station control channel occupying a selected one of the time slots for monitoring the status of the other time slots and for causing the communication circuit and the exchange to complete a connection between a given external communication network port and a given subscriber station over a time slot assigned in response to the monitored status in accordance with a predetermined assignment routine.

Abstract: A modulator for a modem, said modulator being adapted to convert a bit stream, wherein each given number of successive bits defines a symbol, into a phase modulated intermediate frequency (IF) signal, the symbols in the modulator section being phase modulated DPSK conversion. The phase modulated symbols are then digitally filtered to provide a filtered signal comprising time shared, digital in-phase and quadrature phase components that, when converted into an analog signal, provides a modulation signal of a frequency that is centered about a predetermined frequency and deviates therefrom in accordance with the value of the phase modulated symbol. The filtered signal, after being converted to an analog signal is then filtered and passed to a mixer for up conversion to an IF signal.

Abstract: Aqueous guar gum compositions having a very low content of insolubles, the compositions being formed by impregnating free-flowing solid, particulate guar gum with one or more hydrolytic enzymes and thereafter dissolving the particles of guar gum in water.

Abstract: A method of recovering oil from an oil-bearing formation by fractionation, utilizing as oil-recovery means aqueous guar gum compositions having a very low content of insolubles, the compositions being formed by impregnating free-flowing solid, particulate guar gum with one or more hydrolytic enzymes and thereafter dissolving the particles of guar gum in water.

Abstract: The sodium and/or ammonium salts of a mixture of n-alkyl oxyethylated sulfuric acids in aqueous solution, wherein all the compounds have the same molecular formula CH.sub.3 (CH.sub.2).sub.x CH.sub.2 (OCH.sub.2 CH.sub.2).sub.y OSO.sub.3 .sup.- M.sup.+ being either the sodium or ammonium cation, x being an integer from about 6 to 12, and y being an integer from about 1 to 3.5, a major portion of the mixture comprising compounds where x equals 6-8 and a minor portion of the mixture comprising compounds where x equals 10-12; these mixtures being capable of generating foam of relatively large volume and high stability.

Abstract: The sodium and/or ammonium salts of a mixture of n-alkyl oxyethylated sulfuric acids in aqueous solution, wherein all the compounds have the same molecular formula CH.sub.3 (CH.sub.2).sub.x CH.sub.2 (OCH.sub.2 CH.sub.2).sub.y OSO.sub.3.sup.- M.sup.+, M.sup.+ being either the sodium or ammonium cation, x being an integer from about 6 to 12, and y being an integer from about 1 to 3.5, a major portion of the mixture comprising compounds where x equals 6-8 and a minor portion of the mixture comprising compounds where x equals 10-12; these mixtures being capable of generating foam of relatively large volume and high stability.