Abstract: A mobile station (100) that includes a processor (212) that selectively disables at least one station component to reduce electromagnetic noise generated by the station in the frequency range below 20 kHz when the mobile station is operated in the hearing aid compatible mode. The component can be, for example, a display (204), a light (206) or a wireless interface (208). The processor also can optimize characteristics of audio signals transmitted from the mobile station to the hearing aid for reproduction by the hearing aid. For instance, the processor can selectively adjust filter parameters (216) and/or a signal gain (218) applied to audio signals. A user interface (220) having a soft-key can be provided to cycle through various HAC options.

Abstract: A high priority system access technique is provided in which an MS (310) instead of relying on its open loop power level routine to determine its power level for transmission of a system access request uses a higher power level to transmit its access request, such as its RACH preamble. The power level used for transmission of the RACH preamble can be dependent on the particular user and/or in the application (e.g., dispatch, streaming video, etc.). By using a higher power level than the other MSs (520) operating in the system (500), MS (310) has a higher probability of gaining system access and a channel grant in an expeditious fashion. This priority access technique is very helpful for applications that require quick channel grants.

Abstract: The invention concerns a method (200) and system (100) for selectively coupling a communication unit (110) to a hearing enhancement device (112). The method includes the steps of—in the communication unit—selecting (212) between an acoustic coupling setting and an inductive coupling setting, in response to the selecting step, switching (214) an audio output of the communication unit to an acoustic coupling path (136) or an inductive coupling path (138), and outputting (226) through either the acoustic coupling path or the inductive coupling path an audio signal to the hearing enhancement device.

Abstract: A high priority system access technique is provided in which an MS (310) instead of relying on its open loop power level routine to determine its power level for transmission of a system access request uses a higher power level to transmit its access request, such as its RACH preamble. The power level used for transmission of the RACH preamble can be dependent on the particular user and/or in the application (e.g., dispatch, streaming video, etc.). By using a higher power level than the other MSs (520) operating in the system (500), MS (310) has a higher probability of gaining system access and a channel grant in an expeditious fashion. This priority access technique is very helpful for applications that require quick channel grants.

Abstract: A mobile communication device (100) contains a memory (110), a controller (112) and transceiver components (120, 122, 124, 126). When an incoming call signal is received (314), the controller compares the source identifier with various lists (210, 240, 270) stored in the memory. If the source identifier is contained on a rejection list, the call is rejected. If the source identifier is contained on an acceptance list, the call is received normally, unless a do not disturb feature is active. The lists may be fixed or selectable. Selectable lists are configurable by the user of the mobile communication device, whereas fixed list types cannot be changed by the user of the mobile communication device.

Abstract: A method and apparatus for testing of a unit under test (50) by a communication system tester performs loopback tests. During these loopback tests, data transmitted by the unit under test may be stored (21) and sent back to the unit under test. In addition, user defined prestored data (22) may be transmitted to the unit under test. Further, prestored messages (24) and tones (23) may be stored by the communication system tester and transmitted to the unit under test for display on a speaker. An operator (52) may review the output of the speaker and determine whether the test has been properly passed. As a result, the operator may determine whether a fault exits in the receiver or transmitter of the unit under test.

Abstract: A method of conserving battery energy within two-way radios by periodically de-activating the radios for relatively short time periods. The transmission and reception of communication requests are synchronized to occur during concurrent periods of activation. Following receipt of a communication request, requestor and target remain continuously activated for only the duration of the transaction. Synchronization of radio activation and de-activation is maintained by a synchronization beacon transmitted by a base station or a transmitting portable radio.

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 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: In a frequency synthesizer phase locked loop including a reference oscillator, a variable reference divider (.div.M), a sample and hold phase detector, a loop filter, a voltage controlled oscillator and a variable divider (.div.N), a voltage converter for controlling the voltage of a control input to the voltage controlled oscillator is disclosed. In the preferred embodiment, the voltage converter has its input connected to the output of a first reference divider in the variable reference divider (.div.M) and its output connected to a control input (varactor diode) of the voltage controlled oscillator. The voltage converter clamps the divider reference signal from the first reference divider and provides a negative voltage level output to bias the varactor diode of the voltage controlled oscillator. Thus, the tuning range of the frequency synthesizer is increased.

Abstract: A frequency synthesized transceiver capable of tuning to a plurality of communication channels is disclosed. The transceiver includes a receiver section and a transmitter section which are coupled to the synthesizer which generates the appropriate injection signals to achieve tuning. The frequency synthesizer includes a multiposition switch which accesses various addressable memory locations in a programmable read-only memory where the appropriate divisors are stored to cause tuning of the synthesizer to the appropriate communication channel. A zone selector switch enables grouping and easy retrievability of channels. The divisors are supplied to a single synchronous binary swallow counter which works in conjunction with a dual modulus prescaler to monitor the frequency output of the voltage controlled oscillator. A programmable divider coupled to a reference oscillator source is compared with the output of the synchronous counter in a digital and analog phase detector.

Abstract: A frequency synthesized transceiver capable of tuning to a plurality of communication channels is disclosed. The transceiver includes a receiver section and a transmitter section which are coupled to the synthesizer which generates the appropriate injection signals to achieve tuning. The frequency synthesizer includes a multiposition switch which accesses various addressable memory locations in a programmable read-only memory where the appropriate divisors are stored to cause tuning of the synthesizer to the appropriate communication channel. A zone selector switch enables grouping and easy retrievability of channels. The synthesizer includes a priority channel monitoring system utilizing a channel element for rapid sampling. The divisors are supplied to a single synchronous binary swallow counter which works in conjunction with a dual modulus prescaler to monitor the frequency output of the voltage controlled oscillator.