Abstract: The invention comprises a mobile communications device having an attachable device that may be attached to, for example, a belt clip, and a mobile phone communicable coupled with the attachable device. The attachable device comprises a deployable and retractable ear piece and an output node containing a bias signal when the ear piece is deployed. The mobile phone comprises a bias signal port electrically coupled to the output node. The mobile phone activating a communications channel having an incoming transmission upon deployment of the ear piece and deactivating the communications channel upon retraction of the ear piece.

Abstract: A multimedia PDA attachment unit for allowing users to precisely control multimedia equipment in their home or office by simply attaching the multimedia PDA attachment unit to their PDA and downloading the necessary programs and data. The PDA attachment unit comprises means of communication with a PDA and a means of communication with the multimedia equipment to be controlled. The PDA attachment unit utilizes PDA software and database information, which are downloaded from a computer. Computer software allows the user to enter information about the multimedia equipment, which is to be controlled and formats the data used with the PDA software and the PDA attachment unit. The PDA and PDA attachment unit generally have a built in receiver, which receives specific commands from a remote control to control its functionality.

Abstract: A cell-phone retractable earpiece has a phone-wire reel (1) in a reel pocket (2) on a cell phone (3) that is attachable to a user. The phone-wire reel is wind-tensioned to wind the phone wire onto the phone-wire reel in opposition to pulling the phone wire and locking the reel in a desired unwound mode. The earpiece is attached to a user's ear (9) with an ear hook (7) having a sound reproducer (14) with a sound conveyor (15, 19, 20) into a user's ear (9). A microphone retractable appendage (26) is extendible from the phone wire to a position proximate a user's mouth (18). An optional ear clamp (21) can be employed for firm attachment of the earpiece to the user's ear.

Abstract: A wireless spread spectrum base station has a plurality of modems. The modems produce at least one baseband channel signal and a baseband global signal. At least one forward power controller controls a power level of the at least one baseband channel signal. A baseband signal combiner combines the at least one baseband channel and baseband global signals. A radio frequency transmitter modulates to radio frequency and transmits the combined signal. A global power control processor determines a desired transmit power level of the baseband global signal to the desired transmit power level.

Abstract: An alarming device of a vehicle mobile phone hand-free device comprises a microprocessor, a power control circuit, a monitoring device, a mobile phone sensing device, and an alarming device. A mobile phone is installed to a car mobile phone seat having a hand-free device for sensing the mobile phone is placed in or taken out. The microprocessor causes the alarming device to alert the user by speech or lamp signal so as to inform the driver to place the mobile phone on the hand-free device before the car is actuated and take the mobile phone out as the driver leaves from the car. Therefore, the user may use the hand-free device to achieve the safety driving.

Abstract: A method of inventory management is described. Upon activation of a button on a wireless device, the wireless device having a light source and a transceiver with a unique media address corresponding to a unique product, the device broadcasts a first signal including an order command and the unique media address by the transceiver via a wireless medium. A central controller then receives the first signal, identifies the unique media address included in the first signal, and using a database, identifies the unique product associated with the unique media address.

Abstract: Mobile, wireless communications apparatus for transmitting and receiving voice and data signals and being divided into first and second units arranged to be spaced apart but normally operated within a close range and each having a low power transceiver for communication between the first and second unit over a low power radio link. The first unit has a more powerful transmitter and an antenna for receiving and transmitting signals to a remote location, typically through a base station forming part of a cellular network. The second unit is significantly smaller than the first unit and incorporates miniaturized elements including a display, key pad, microphone speaker and micro controller, together with the aforementioned low power transceiver. The battery supply in the second unit is significantly smaller than that provided in the first unit, the second unit being designed to be a size of the order of a conventional wrist watch and being capable of being worn on the wrist of a user.

Abstract: A locating device for use with a portable two-way radio transceiver, for enabling the radio transceiver to transmit a locating signal containing position locating information. The locating device comprises a sensor (510) for sensing a signal containing position locating information, a memory (504) for storing position locating information obtained from the signal, a communications device (507) for communicating with the radio transceiver, a control device (504) for controlling the radio transceiver via the communications device (507) and an activating device (517) for activating the locating device. When the locating device is activated, the control device (504) causes the radio transceiver to transmit a locating signal containing the position locating information stored in the memory (504).

Abstract: A handheld device comprises a housing and an optical reader supported by the housing. The housing can include a corner portion at which the optical reader is accessible. Alternatively, the housing can define a major exterior surface at which the optical reader is accessible. The optical reader can include a scanning beam reader responsive to an orientation of the handheld device.

Abstract: Control device for a communication system of an aircraft, in particular of a transport plane.

Abstract: A docking device, also known as a cradle, used in docking a PDA (personal digital assistant) for data synchronization with a host computer, includes an antenna for providing cordless communication between the PDA and the host computer. The cordless communication is established without docking the PDA in the cradle and without the use of a wireless network or carrier. Thus, both economical and convenient data communication can be performed between the PDA and the host computer using the cradle.

Abstract: A wearable device comprises one or more circuit substrates comprising electrically conductive parts, a radio unit and a loop antenna coupled to the radio unit. The loop antenna comprises a conductor formed into a loop, wherein the electrically conductive parts of at least one of said one or more circuit substrates substantially act as a ground plane for the loop antenna. Said at least one circuit substrate is positioned substantially on the same plane with the loop and such that at least the electrically conductive parts of said at least one circuit substrate are within an area defined by the loop when said at least one circuit substrate and the loop are observed perpendicularly with respect to a plane of the loop in order to minimize the ground plane effect of the electrically conductive parts of said at least one circuit substrate on the loop antenna.

Abstract: A wireless network telephone system using an embedded processor as the CPU to provide a portable and expandable network telephone system.

Abstract: A handheld device comprises a housing and an optical reader supported by the housing. The housing can include a corner portion at which the optical reader is accessible. Alternatively, the housing can define a major exterior surface at which the optical reader is accessible. The optical reader can include a scanning beam reader responsive to an orientation of the handheld device.

Abstract: An apparatus and method are provided for transmitting audio signals from an auxiliary source such as a satellite broadcast receiver or a CD or cassette player to a radio receiver located, for example, in a vehicle, using a wireless link. The apparatus comprises a scanning device for locating open radio frequencies in the RF spectrum of the radio receiver. The apparatus displays plural RF channel options on a display device and provides a selection device with which a user selects an RF channel. The apparatus modulates the audio signals using the selected radio frequency, and the user tunes the vehicle radio receiver to the selected RF channel. The scanning device continuously scans for open RF channels and monitors the quality of the RF channel already selected for use as the wireless link. The apparatus provides the user with an indication to select another open channel when the RF channel in use degrades.

Abstract: The portable telephone is provided with an antenna serving as both transmitting and receiving antennas, a radio unit composed of a transmitter and a receiver, a display for displaying telephone numbers, an interchanging key for interchanging functional modes, a key-operating unit including numerical keys, and a control unit. A communicative mode related to a telephonic communication and a noncommunicative mode (a mode unrelated to communication) are selected alternately in accordance with an operation of the interchanging key. When the noncommunicative mode is selected, the radio unit stops functioning and a noncommunicative mode indicating lamp lights up to notify persons around the portable telephone that it is functioning in the noncommunicative mode. According to the aforementioned structure, the persons around the portable telephone will permit a user to use it in the noncommunicative mode.

Abstract: A light assembly housing a light source is provided to be removably attachable to a radio unit designed to be removably attachable to a battery assembly. The light assembly may be positioned between the radio unit and battery assembly, and is capable of conducting power from the battery assembly to the radio unit.

Abstract: A radio telephone (1) in accordance with the invention comprises at least a power supply (65), radio part (4), antenna (5) of the radio part, and a user interface having at least one microphone (9, 14), at least one earpiece (8, 13), means (6) for making a call and means (15) for answering a call. The radio telephone (1) is divided at least into a first part (2) and a second part (3). The first part (2) comprises at least the power supply (65), radio part (4), antenna (5) of the radio part, and means (21, 28) for communicating on the first link communication (LINK1) with the second part (3). The second part (3) comprises at least the means (15) for answering the call, and means (33, 39) for communicating with the first part (2).

Abstract: Apparatus, and an associated method, for radio receiver circuitry operable in multi-modes to receive signals generated during operation of a multiple number of radio communication systems. The receiver circuitry is divided into receive chain portions which are selectably utilized depending upon which of the multiple number of the radio communication systems in which communications are to be effectuated. Selected combinations of the receive chain portions are formed, depending upon which of the modes in which the receiver circuitry is to be operable. Different combinations of the receive chain portions permit sharing of receive chain portions thereby to reduce the required number of circuit elements to form the multi-mode receiver circuitry. In one implementation, the radio receiver circuitry forms the receive portion of a dual-band, tri-mode mobile station operable in a selected one of three different cellular communication systems.

Abstract: A communications terminal handset having a translucent outer casing and a light source arranged for illumination of a substantial area of the casing.

Abstract: A portable radio communication apparatus, includes a main body, and a sub-apparatus. The main body communicates with a partner. The sub-apparatus is mechanically separated from the main body. The main body and the sub-apparatus communicate with each other wirelessly. The sub-apparatus includes a call signal arrival display unit and a response unit. When the main body gets a call signal from the partner, the main body transmits a call arrival signal to the sub-apparatus. The main body transmits a response message to the partner in response to a response signal. The call signal arrival display unit sends a notice that the main body gets the call signal in response to the call arrival signal. The response unit outputs the response signal to the main body in response to an operation performed on the response unit.

Abstract: An information processor capable of recognizing whether the possessor (user) of the information processor is carrying the information processor or located in the vicinity of the information processor. The information processor performs a suitable processing operation according to the possessor's (user's) carrying or non-carrying condition. The information processor has a transmitting section to transmit a signal receivable only in the range of a predetermined distance to a wristwatch type information processor previously assigned, a receiving section to receive a signal sent from the wristwatch type information processor in response to the signal transmitted by the transmitting section, a decision section to make a determination as to whether the reply signal has been received by the receiving section, and a processing operation control section to execute a predetermined processing operation depending upon the result of the determination made by the decision circuit.

Abstract: This invention provides a method for reducing FM interference in an in-band on-channel digital audio broadcasting system. The method includes the steps of receiving a composite signal including a signal of interest and an interfering signal and normalizing the composite signal to produce a normalized composite signal. The composite signal is then multiplied by the complex conjugate of the normalized composite signal to produce a real signal. Then the real signal is filtered and the resulting filtered signal is multiplied by the normalized composite signal to produce an output signal. The adverse effects of the interfering signal in the output signal are reduced with respect to the magnitude of the signal of interest reducing FM interference in an in-band on-channel digital audio broadcasting system, thereby making it easier to detect the signal of interest.

Abstract: A location is provided with a fixed wireless transceiver. The wireless transceiver is coupled to a land-line that connects the location to the local exchange carrier's central office. The wireless device is powered by power received from a central office over the land-line connection.

Abstract: A communication system (20) is provided with multiple purpose personal communication devices (50 and 150). Each communication device (50 and 150) includes a touch-sensitive visual display (60 and 160) to communicate text and graphic information to and from the user and for operating the communication device (50 and 150). Voice activation (78) and voice control capabilities (76) are included within communication devices (50 and 150) to perform the same functions as the touch-sensitive visual display (60 and 160). The communication device includes a built-in modem (82), audio input and output (52 and 53), telephone jacks (86), and wireless communication (90). A plurality of application modules (100) are used with personal communication devices (50 and 150) to perform a wide variety of communication functions such as information retrievable, on-line data base services, electronic and voice mail.

Abstract: A power amplifier circuit has a driver amplifier stage including a low band driver amplifier and a high band driver amplifier. A final amplifier stage includes a linear mode amplifier for amplifying digitally modulated signals and a saturated (nonlinear) mode amplifier for amplifying frequency modulated (analog) signals. A switching network interconnects the driver amplifier stage and the final amplifier stage. Depending on the desired mode of operation, an appropriate driver amplifier can be coupled to an appropriate final amplifier to most effectively and efficiently amplify analog or digital RF signals in either of a plurality of frequency bands. A matching circuit is coupled to the linear mode final amplifier for impedance matching and for separating D-AMPS (800 MHz band) and PCS (1900 MHz band) digital signals. A power impedance matching circuit is coupled to the output of the saturated mode final amplifier.

Abstract: The present invention provides a cheap handsfree unit which can prevent the howling phenomenon and reduce the input sound from the loud-speaker into the microphone in both the analog and digital modes. A reception side comprises a signal level adjusting circuit constituted by a switch circuit and attenuators, and a transmission side comprises a signal level adjusting circuit constituted by a switch circuit and attenuators, to introduce the attenuation of 15 dB or 30 dB in response to the analog or digital mode. A voice switch is constituted so that the analog reception signal and the analog transmission signal are rectified respectively by rectifiers, the levels of both signals are compared by a comparator, and either switch or switch having a higher input signal level becomes conductive as a result of the comparison. The attenuation is introduced on the basis of the communication mode, only to either the analog reception signal or analog transmission signal having a smaller signal intensity.

Abstract: A dual system communicator includes an electronic analog communicator and a removeably attached power source. The analog communicator includes analog signal transceiving electronics. The power source includes digital signal transceiving electronics. The analog communicator and the power source are wirelessly interfaced for communication between the digital signal transceiving electronics and the analog signal transceiving electronics. The dual system communicator is operational as a standard analog communicator or as a communicator capable of receiving digital signals which are converted to analog signals by a converter and transmitting analog signals which are converted into digital signals.

Abstract: Mobile radio systems with mobile switching centers to which at least one private branch exchange for providing wireline subscriber lines is connected, are known. The branch exchanges require an expensive switching technology and are not capable of providing mobile-radio-specific service features at the wireline subscriber terminals. For the purpose of providing a mobile radio system (MRS) of simple construction accessible also to wireline subscribers, a mobile switching center (MSC) is proposed comprising an interface unit (IF) for interfacing to a concentrator (FSU) which combines a plurality of subscriber lines of wireline subscriber terminals (T1 to Tn). Accordingly, each of the wireline subscriber terminals is connected in such a way that it is treated like a mobile radio terminal, and offered the same available service options.

Abstract: A multimode radio communication terminal includes a tunable source of transmit and/or receive local oscillator signals for transmitting and/or receiving channels of different frequency bands in at least two radio communication systems. The terminal includes, downstream of the tunable source, a switchable frequency changer implementing a fixed frequency change and selectively insertable so that, the source responding directly to the requirements of one radio communication system, insertion of the frequency changer renders it capable of responding to the requirements of another radio communication system using different frequency bands. This is achieved by virtue of a particular change to the frequency produced by the tunable source, effected by the frequency changer.

Abstract: A converted analog radio (71) is disclosed for converting an analog microwave hop (70) to a new operating frequency. The converted analog radio (71) comprises an analog radio (72) operable to communicate microwave signals at a first frequency, a digital radio (74) operable to communicate microwave signals at a second frequency, and a conversion assembly (76). Reception components (40, 42, 44) and transmission components (56, 58, 60, 62) of the digital radio (74) are used to communicate at the new operating frequency. Intermediate frequency components (26, 28, 30, 32) of the analog radio (72) are used to process intermediate frequency signals, and the conversion assembly (76) is used to convert from the prior operating frequency to an intermediate frequency for use by the transmission components (56, 58, 60, 62) of the digital radio (74).

Abstract: A digital submodule is included in a software programmable common receive module for receiving IF signals and producing a serial bit stream. The digital submodule is programmable based on a selected application of a plurality of radio applications and, if present, a selected function of a plurality of functions of the selected radio application. The digital submodule may include an analog to digital converter for converting IF signals received from an analog submodule into digital signals. The digital signals are supplied to a programmable signal processing unit which is configured, according to the selected radio application and, if present, the selected function, to perform control functions, processing and analysis of the digital signals and generate output signals. The output signals are then formatted by a formatting unit producing formatted digital signals. The formatted digital signals are then supplied to a system bus.

Abstract: A system for combining AM and FM transmissions. In-band, On-channel, FM Digital Audio Broadcast (IBOC FM-DAB) allows simultaneous transmission of DAB and FM over existing FM allocations without interfering with conventional analog FM signals. The utility of existing FM spectrum allocations is therefore enhanced.

Abstract: A mobile phone set includes a base unit and at least one handset belonging to the base unit. In the base unit, a receiving section 11 receives a first modulated wave S.sub.1 which is a digital modulated wave from TX 3, and a demodulating section 12 demodulates the received wave, and further a decoding section 13 decodes the demodulated wave. Further, a detecting section 17 detects the demodulated wave. Further, a detecting section 17 detects that the decoded signal is of a calling signal for the handsets 2-1 and 2-2 associated with the base unit, and after the detection a controlling section 25 instructs a D/A converting section 14 to D/a convert a digital signal decoded by the decoding section 13 to an analog signal and a modulating section 15 to modulate the analog signal. A transmitting section 16 transmits a second modulated wave S.sub.2 as the analog modulated wave to the handset 2-1 or 2-2. Further, in the base unit 1, a receiving section 18 receives a third modulated wave S.sub.

Abstract: The present invention relates to a wireless apparatus for transferring information between computers. The communication device uses a diskette that transmits and receives information by using radio frequency. The diskette includes receiving and transmitting circuitry which is used in conjunction with software to facilitate the file transfer.

Abstract: The invention relates to a transceiver for generating complex I/Q-signals on a transmission frequency (f.sub.TX) and for receiving them on a reception frequency (f.sub.RX). The device comprises a first frequency synthesizer (41) for forming a first mixer signal (f.sub.LI) for the mixer (42) of the first branch that mixes the I-component of the received signal into a lower-frequency I-signal, and a second frequency synthesizer (411, 49, 46) for forming a second mixer signal (f.sub.LQ) for the mixer (421) of the second branch that mixes the Q-component of the received signal into a lower-frequency Q-signal. The device further comprises control means (45) first for directing the phase of the first (f.sub.LI) and the second (f.sub.LQ) mixer signals into the same phase in the mixing effects thereof and, thereafter, into a 90 degree mutual phase shift in the mixing effects thereof when receiving signals for bringing the lower-frequency I- and Q-signals into a 90 degree mutual phase shift.

Abstract: A millimeter-wave wireless data transmission link is utilized to interconnect multiple electronic components within an enclosed electronic system. More specifically, an electronic apparatus includes a housing, a plurality of separated electronic components located within the housing, and a plurality of millimeter-wave transmit/receive integrated circuit devices, each coupled to a corresponding one of the separated electronic components. Data is transmitted between the plurality of separated electronic components via the millimeter-wave transmit/receive integrated circuit components, each of which includes one or more transmit/receive circuits preferably operating at frequencies above 35 GHz. The transmit and receiving frequencies of the transmit/receive integrated circuit devices can be dynamically set in memory to enable transmission links to be easily reconfigured.

Abstract: A digital system accommodates analog communications, thus avoiding the need for separate subsystems each dedicated to either analog or digital communications. The system includes a receive circuit for converting received signals into an intermediate frequency, a transmit circuit for modulating and transmitting signals and signal processors for processing the intermediate frequency signals and the signals to be transmitted, wherein the signals can be processed into digital or analog format using substantially the same circuitry.

Abstract: A mobile terminal apparatus that operates in both the cellular and satellite networks. The terminal device has five different operating modes. It operates in a satellite only mode, a cellular only mode, an autoroam with satellite priority mode, an autoroam with cellular priority mode, and autoroam with cellular home location register (HLR) priority mode. The terminal apparatus monitors the cellular operation and satellite operation concomitantly. When a call is in progress in the cellular system, a seamless handoff may be effected to the satellite system.

Abstract: In accordance with IS-136 standard, an analog wireless signal and a digitally encoded wireless signal can be received by a remote telecommunicating device. The remote device can differentiate between the analog wireless signal and the digitally encoded wireless signal by measuring the average energy of the signal in the portion of the baseband signal that is expected to contain the Supervisory Audio Tone signal, and the portion of the baseband signal that is expected to be outside of the audio band for an analog signal. The average energy of the portion outside of the audio band is subtracted from the average energy of the SAT signal. The difference is compared to a threshold, and based upon the comparison, the characteristic of the received wireless signal, i.e. analog or digital, is determined.

Abstract: A system and method are disclosed for bidirectionally coupling a first satellite communication system to a second satellite communication system, wherein the first and second systems operate with different protocols. In a presently preferred embodiment of this invention the first system uses a spread spectrum (SS), code division multiple access (CDMA) technique wherein the satellites serve as simple `bent pipe` repeaters for relaying communications between a user and a gateway. The second satellite communication system may be any other type of system having at least one characteristic that precludes direct communication between the first and the second systems. In an exemplary embodiment the second system uses a time division multiple access (TDMA) technique, and furthermore enables direct satellite-to-satellite communication links.

Abstract: A radio communication device which is capable of effecting communications in different communication systems and is highly advantageous economically has a main communication unit capable of effecting communications in a first digital cellular communication system (GSM), and an additional unit to be attached to said main communication unit for effecting communications in a second digital cellular communication system (PCN) which differs from said first digital cellular communication system. The main communication unit includes variable-bandwidth filters compatible with both GSM and PCN. The additional unit comprises a power amplifier, and the main communication unit has a power amplifier. Switching can be made between these power amplifiers to make the radio transmission device compatible with both GSM and PCN. The radio communication device has many components shared by GSM and PCN and hence is highly economical.

Abstract: A position monitoring system having a position finder subsystem connected via a cellular telephone to a central monitoring station, a receive/transmit device carried with the position monitoring subsystem. A remote personal signalling subsystem comprising an RF coder modulator for transmitting a coded RF signal, and operating switch for activating the RF coder modulator. A receiver/transmit device is carried with a position monitoring subsystem for receiving the coded RF signal, decoding same and transmitting a coded RF acknowledgement signal. The remote personal signalling subsystem includes an RF decoder and demodulator for receiving and decoding the coded RF acknowledgement signal and a tactile signalling device is operated by the RF decoder and demodulator upon receipt of the coded RF acknowledgement signal and provides a tactile signal to a user that the RF coded signal had been properly received by the position finding subsystem.

Abstract: The invention relates to an assembly for radio communication containing all the electronic components necessary for radio transmission/reception, which can alternatively be connected to a device for voice communication and to a device for data communication.The device for voice communication with the assembly (which, according to the preferred embodiment of the invention, is implemented on a reduced dimension PCMCIA integrated circuit card) plugged therein, has more or less the same dimension and the same weight of a usual cellular phone device.When radio data transmission is desired the PCMCIA integrated circuit card is to be unplugged from the telephone handset and plugged into a data processing device properly arranged. In this way the data processing device is provided with the capability of radio transmitting and receiving data.

Abstract: A removable panel has a plurality of operation buttons for operating a car stereo. A cellular telephone system operated by the operation buttons is provided in the panel. A controller is provided in the panel for rendering the car stereo inoperative in response to an instruction received through the cellular telephone system.

Abstract: A mobile communications system in accordance with the invention comprises primary and secondary wireless digital communications networks. The system also comprises a wireless mobile messaging unit. The primary wireless digital communications network operates on a first communications channel using a reserved time slot protocol having discrete time slots reserved for data transmissions to the mobile messaging unit. The secondary wireless digital communications network operates on a second communications channel using a continuous downlink protocol under which data transmissions to the mobile messaging unit might take place at any time. The wireless mobile messaging unit has channel selection logic operatively connected to tune the mobile messaging unit to the first communications channel during the discrete time slots and to the second communications channel during other times.

Abstract: A digital satellite communication system including a local terminal coupled to a radio wireline interface through a radio satellite network. The radio wireline interface connects the radio satellite network to a public switched telephone network and a remote communication terminal. The system includes a novel method of establishing an end-to-end communication channel between local and remote terminals wherein the local terminal establishes a direct digital channel between itself and the radio wireline interface and transmits a message describing its signaling capabilities to the radio wireline interface. The radio wireline interface then trains its modem with the modem of the remote terminal such that the signaling capabilities of the local terminal are not violated. By moving the modem training procedure to the radio wireline interface, modem training response delays caused by the radio satellite network do not affect the success of establishing the end-to-end communication channel.

Abstract: An automatic level control circuit for cellular telephone transmitters which is compatible with both existing analog cellular service and expected next generation digital TDMA service. The circuit automatically and dynamically changes modes to maintain communication when a mobile subscriber moves from one type of service to another. In a first mode of operation, which is compatible with existing analog cellular service, the circuit provides a closed loop negative feedback circuit which produces a control signal for continuously controlling the output power level of the transmitter amplifier. In a second mode of operation, which is compatible with proposed digital TDMA service, the circuit operates to alternately close the negative feedback loop during the periods when the transmitter is permitted to transmit (assigned TDMA frames) and open the loop during other periods when the transmitter is turned off. When the loop is opened, the invention temporarily stores the magnitude of the control signal.

Abstract: A power amplifier used in a portable, radio frequency transmitter is switched between different modes of operation when transmitting differently modulated carriers. The first mode of operation corresponds to amplitude modulation (AM), while a second mode corresponds to angle modulation techniques such as frequency modulation (FM). A switching network alters the impedance of the power amplifier to match network for matching the impedance of the transmitter antenna in order to achieve maximum efficiency in each mode of operation. Various switching methods and impedance matching circuits are disclosed.

Abstract: When remote control data has been input during calling in analog mode, a mobile radio communication apparatus according to the invention outputs a predetermined first voice frequency signal indicative of the remote control data and transmitting the signal to a radio link, and outputs the first voice frequency signal. Further, when remote control data has been input during calling in digital mode, the mobile radio communication apparatus outputs message data indicative of the remote control data and transmitting the message data to a radio link, generates a second voice frequency signal corresponding to the input remote control data and also the first voice frequency signal, and outputs the second voice frequency signal before the message data is transmitted.