Abstract: A tuning circuit for a reference oscillator (200) including voltage variable capacitors (222, 224) in a back to back configuration and providing a control terminal for voltage controlled tuning of the reference oscillator (200). Also included in the tuning circuit is a modulation bias circuit for modulating the reference oscillator (200).

Abstract: An offset transmission line coupler (115) for a transmitter output signal (123) generated by an RF signal amplifier (103) includes a through-path transmission line (201) and a coupled-path transmission line (202) electromagnetically coupled thereto by multiple serpentine-like portions (such as portions 641,642, 643 and 644 in FIG. 6), which are disposed on opposite sides of the through-path transmission line (201) for enhancing coupling sensitivity and eliminating degradation in the amount of coupling due to variations in the transmission line plating registration. Offset portions (641,643) on one side of the through-path transmission line (201) provide substantially the same amount of coupling as the offset portions (642,643) on the other side of the through-path transmission line (201).

Abstract: A cellular cordless telephone (10) operates with both a cordless base station (180) and a cellular base station (190) and cellular control terminal (196). In one embodiment (FIG. 2 ), a cellular cordless telephone (100) includes a cellular transceiver (120), antenna (128), keyboard (140), a display (180), handset (160), and microcomputer (130) together with a cordless transceiver (110) and antenna (118), all of which may be in a single housing. In another embodiment (FIG. 3 ), a cellular cordless telephone (200) includes a cellular telephone (220) and a cordless telephone transceiver (210) which may be a plugable module. Whenever cellular cordless telephone (10) is within range of cordless base station (180), telephone calls may be made over the cordless radio channel or transferred from the cellular radio channels to the cordless radio channel.

Abstract: The process of the present invention error corrects sub-audible data words that have been transmitted over a voice channel. A data word may be transmitted up to three times if an acknowledge is not received by the transmitter. If any of the three possible repeats of the received data word are decodable, an acknowledgment is transmitted. If all three repeats of the data word contain uncorrectable errors, a bitwise majority vote is performed on the three data words. If the result of the majority vote is decodable, an acknowledgement is transmitted to the sender.

Abstract: A transmission line coupler (115) for a transmitter output signal (123) generated by an RF signal amplifier (103) includes a through-path transmission line (201) and a coupled-path transmission line (202) electromagnetically coupled thereto by multiple serpentine-like portions (such as portions 641, 642, 643 and 644 in FIG. 6 ), which are disposed on opposite sides of the through-path transmission line (201) for enhancing coupling sensitivity and eliminating degradation in the amount of coupling due to variations in the transmission line plating registration. Offset portions (641, 643) on one side of the through-path transmission line (201) provide substantially the same amount of coupling as the offset portions (642,643) on the other side of the through-path transmission line (201).

Abstract: A dual-mode RF signal power amplifier combining network is comprised of two branches, each having a power amplifier (200 and 201). The first branch contains a non-linear mode power amplifier (200) while the second branch contains a linear mode power amplifier (201). The non-linear mode branch also has an RF switch (210). Both branches are coupled to a common output node (220). The common node (220) is coupled to a filter (107) before going to an antenna (106). The non-linear mode power amplifier (200) operates when an FM signal is to be amplified, while the linear amplifier (201) is biased in an off state. The linear mode power amplifier (201) operates when a digital signal is to be amplified, while the non-linear amplifier (200) is biased in an off state. The RF switch (210) removes the non-linear amplifier (200) from the circuit to prevent loading the on state linear amplifier (201).

Abstract: A dielectric filter having at least two adjacently-positioned resonators extended therethrough. The two adjacently-positioned resonators are of trapezoidal cross-sections to form thereby trapezoidal resonators. By suitable selection of the configurations of such resonators, the amount of coupling between such adjacent resonators may be controlled. For instance, a minor base side of the first trapezoidal resonator may be positioned adjacent to a corresponding minor base side of the adjacent trapezoidal resonator, or a major base side of the first trapezoidal resonator may be positioned adjacent to a major base side of the adjacent trapezoidal resonator, or a minor base side of the first trapezoidal resonator may be positioned adjacent to a major base side of the second trapezoidal resonator. Such electromagnetic coupling between the adjacent resonators is controlled by the relative configurations of such resonators rather than by increasing the spacings between such adjacent resonators.

Abstract: A system and method for correcting for Rayleigh interference of a signal transmitted upon a multi-path channel. The system adaptively calculates values of channel gain and noise variance of the channel upon which the signal is transmitted, and generates signals indicative of such calculations which are supplied to a decoder. The system may be utilized to form a portion of a coherent, or noncoherent receiver which receives encoded and differentially-encoded signals.

Abstract: A fastener for fastening at least two tandemly-positioned surfaces, such as opposing surfaces of a housing assembly, theretogether. The fastener includes first and second hook members which are affixed in a defined relationship with top and bottom surfaces which are to be affixed theretogether. A clip formed of a multi-slotted plate member having slotted openings of dimensions corresponding to the dimensions of the hook members is fastened about the hook members to affix the hook members, and hence, the top and bottom surfaces theretogether. By affixing the clip to a substrate positioned between the top and bottom surfaces, the single clip may be utilized to fasten the substrate in position between the top and bottom surfaces.

Abstract: A cellular cordless telephone (10) operates with both a cordless base station (180) and a cellular base station (190) and cellular control terminal (196). In one embodiment (FIG. 2), a cellular cordless telephone (100) includes a cellular transceiver (120), antenna (128), keyboard (140), a display (180), handset (160), and microcomputer (130) together with a cordless transceiver (110) and antenna (118), all of which may be in a single housing. In another embodiment (FIG. 3), a cellular cordless telephone (200) includes a cellular telephone (220) and a cordless telephone transceiver (210) which may be a plugable module. Whenever cellular cordless telephone (10) is within range of cordless base station (180), telephone calls may be made over the cordless radio channel or transferred from the cellular radio channels to the cordless radio channel.

Abstract: A method and means of automatically accessing several types of radio systems is described. The present invention allows a subscriber unit, which is normally operative in a operator selected radio system, to establish communication with an alternate system if a operator selected system cannot be found. The alternate system may be a conventional single channel mobile relay system or trunked radio system in which the subscriber is authorized to operate. Once communications are established with an alternate communication system, the present invention will periodically attempt to establish communication with the operator selected system while simultaneously attempting to be assigned a higher priority channel in the alternate communication systems according to a priority scan list. Further, the present invention will automatically ignore certain channels which are dedicated for car-to-car use.

Abstract: A unique method and apparatus processes and validates Manchester-coded data transmitted on a communications channel and containing a synchronization word and a data word including a plurality of data bits and coded according to a predetermined BCH error correcting code. Each data bit has a binary state determined by a left half non-return-to zero (NRZ) bit sample and a right half NRZ bit sample.