Abstract: A communication system (100) is provided comprising a communication resource controller (110) which synchronously communicates with a communication unit (120). Communication range of the system is extended by adjusting transmission timing of a channel access request based on position information received from a global positioning system.

Abstract: A method for adjusting the transmitter power of a subscriber unit includes the steps of determining noise characteristic of a receiver site, measuring strength of a signal received from the subscriber, determining a power adjust value based on the noise characteristic and the received signal strength. The transmit power of the subscriber unit is adjusted according to the power adjust value.

Abstract: A communication system (100) is provided comprising a communication resource controller (110) wherein the likelihood of success for establishing synchronous digital communication with a communication unit (120) is substantially greater than the likelihood of success for establishing analog communication. The communication unit may establish analog communication after the communication resource controller receives a digital access code from the communication unit. The analog communication is deferred until the received signal strength from the communication resource controller is above a predetermined level which makes the establishment of analog communication substantially likely.

Abstract: An adhesive pad (100) is provided which has a shrinkable member (130) disposed on an adhesive member, including a film (110), and an adhesive layer (120). The shrinkable member (130) is responsive to heat to expose a portion of an adhesive surface (126) in response to heat.

Abstract: A battery powered transmitter (330) is provided which includes a power amplifier (332) having controllable output power and current drain, a temperature sensor (300) and a controller (309). The output power of the power amplifier (332) is reduced when the ambient temperature drops below a predetermined threshold in order to reduce current drain from a battery (350) in cold temperatures.

Abstract: A time division multiplexed system is disclosed in which communication messages among a wide area site and a plurality of substantially scattered local sites are communicated on a radio frequency channel which is divided into a plurality of time slots, wherein at least one of the time slots is further divided into a plurality of subslots. Communication units operating in the wide area site communicate communication messages during the time slots, and the communication units operating in the local sites communicate communication messages during the subslots which are assigned to each of the local sites.

Abstract: A TDM cellular communication (100) system includes a plurality of repeaters (102) each providing communication coverage for a cell site. A plurality of communication units communicate with the repeaters. The communication units are handed off from one cell site to another by measuring the range of the communication units from the repeaters. If the range exceeds a predetermined range the received signal quality of the adjacent cell site repeaters are measured. An available cell site which provides the best received signal quality is selected by the communication unit for hand off.

Abstract: A linear amplifier comprising a feedback loop is stabilized by determining phase error between an error signal and a feedback signal and shifting the phase of a forward signal accordingly.

Abstract: A radio device (10) receives optical control signals from a remote control apparatus (22). In one embodiment, both the radio device and remote control apparatus include optical transmitters (58) and receivers (60) so that control and information signals may provided to and received from the radio's operator. In another embodiment, the radio () provides a light signal to the remote control apparatus () that either permits or prohibits (80) the light signal's return to the radio. In this way, the presence or absence of the return light signal comprises optical control signals to control the radio's operation.

Abstract: Battery capacity in a portable two-way radio is determined by measuring the voltage across the battery at predetermined time intervals and determining battery voltage slopes. Each battery voltage slope is compared with a previously determined battery voltage slope and the battery capacity is determined by analyzing the changing pattern of the battery voltage slopes.

Abstract: A molded sealing pad for a radio housing assembly is provided which has an outer sealing portion for sealing the outer periphery of the radio housing, and an inner sealing portion for sealing inner apertures of the housing assembly. The outer sealing portion includes push button actuation elements which may be actuated by exerting a horizontal actution force, and the inner sealing portion includes key pad buttons which may be actuated by exerting a vertical actuation force.

Abstract: A battery powered TDM (or combined TDM/FDM) communication device (104, 105) operates within a TDM communication system (100) having a communication channel arranged into repetitive time frames (401) each having a plurality of slots. At least two of these slots (404) are allocated for communicating signalling and control information. To conserve energy, the battery powered communication device operates in a first mode (i.e., the energy saving mode) to shut down non-essential circuits for a predetermined time interval, awaking to monitor only one of the two control slots. In this way signalling and control information may be received. When not operating in the energy saving mode, the battery powered communication device operates in a second mode (i.e., a fast access mode) to monitor both of the control slots (404).

Abstract: An impedance matching transformer includes a dielectric having a varying thickness between opposing surfaces. A transmission conductor and a return conductor are formed on the opposing surfaces. The impedance transformation between a first terminal and a second terminal is proportional to the thickness variation of the dielectric.

Abstract: A transmission line filter is provided which includes a first resonator having open ends being coupled to a second resonator disposed on a substrate. A transmission zero frequency is tuned by means of a varactor which is coupled between the first and the second resonator. The first resonator includes a terminal for applying a control voltage to the varactor for varying its capacitance.

Abstract: A vision system for a robotic station which includes a camera for locating an object to be placed. The camera is mounted to a robotic manipulator which includes a gripper for holding the object. A mirror assembly deflects the images of the object such that it is captured by the camera. The mirror assembly comprises two face-to-face mirrors being angled at 45 degrees.

Abstract: An oscillator circuit is tunable by a tuning circuit which includes a spiral inductor disposed on a ferrite substrate. The oscillator circuit is tuned or modulated by varying a current through the spiral inductor.

Abstract: A dual function rotary assembly (100) functions as a potentiometer and a momentary switch. The dual function assembly (100) includes a rotary shaft (106) that when rotated to a predetermined position, such as its final rotational position, may be pulled to provide a momentary contact between two switching terminals (116, 126).

Abstract: A four port antenna switch (300) for switching a receive port (320) and a transmit port (310) between a remote antenna port (330) and a standard antenna port (340) is provided. The switching actions of the receive port (320) between the remote antenna port (330) and the standard antenna port (340) is provided by a relay (350) under the control of a relay controller (352, 354, 400). The switching of the transmit port (310) between the standard antenna port (340) and the remote antenna port (330) is provided by diode switches (360, 370) under the control of diode switch controllers (332, 324, 312, 314, 400). The switching actions of the relay (350) and the diode switches (370, and 360) is complementary to each other, wherein sufficient isolation between the receive port and the transmit port is provided. In this arrangement, a low power relay may be used because the relay only switches low level received signals, and the high power transmit signals are switched by the pins.