Abstract: A method generally improves the frequency accuracy in a communications system without requiring the use of accurate frequency references in all of the stations or types of stations. An accurate frequency reference is utilized in one of the stations or station types. The reference frequencies of the remaining stations or station types can be adjusted based upon the accurate reference frequency in one of the stations.

Abstract: A two-way radio having a receiver (20) for receiving a radio signal including a voice message, a storage element (45) coupled to the receiver for storing the voice message received, a voice input device (49) for inputting voice messages, a user-actuable selection input (15) for receiving a user input to change between a transmit mode and a repeat mode and a transmitter (21) selectively coupled to the storage element and the voice input device for selectively transmitting input voice messages when in the transmit mode and retransmitting the stored voice message when in the repeat mode. A detection circuit (47) detects the radio signal and a control circuit (50) coupled to the receiver, the transmitter and the detection circuit operates in the repeat mode for activating the transmitter (21) to retransmit the voice message when the detection circuit (47) detects that the radio signal ends.

Abstract: A network system of programmable, identification, locating, monitoring and processing fixed position (FPN) and movable tag nodes, which provides direct inter-node communication capability without a central processor. The individual nodes include microprocessor elements, pre-programmed to recognize external environmental conditions and to logically act on the basis of recognized condition parameters, and where appropriate, to communicate with other nodes for network action. Each node comprises an IC having three independent processors which share a common memory and control circuitry but with separate sets of registers. A first processor (CPU) provides media access control and communication between the nodes and includes transceiver elements for receiving and transmitting information.

Abstract: A device for controlling an accessory based on the detection of transmissions of appropriate input frequency exceeding a minimum threshold amplitude from a nearby cellular telephone. The device includes an independent receiver for directly detecting the transmissions from the nearby cellular telephone and a controller connected to the receiver for controlling the accessory device based on the detection of the transmission from the nearby cellular phone. The independent receiver includes a frequency discriminator of a totally digital design for detecting a signal which is greater than a predetermined threshold frequency and amplitude.

Abstract: A spread spectrum communication apparatus comprises a correlator for correlating a received signal and a reference signal, a synchronizing circuit for synchronizing codes for spread spectrum communication according to a correlation output of the correlator, a controller for controlling a transmission power according to the output of the correlator, and a detector for detecting the output of the correlator. The synchronizing circuit synchronizes the codes according to the output of the correlator detected by the detector. The controller controls the transmission power according to the output of the correlator detected by the detector.

Abstract: An interactive individual location and monitoring system includes a central monitoring system for maintaining health, location, and other data with respect to an individual. A watch unit carried by the individual receives medical and other information selected by and inputted directly from the individual. The watch unit broadcasts the medical and other information locally by radio in a region near the individual. A belt worn pod unit is worn by the individual, including a transponder for receiving the information from the watch unit. The pod unit transmits the information to the central monitoring system. The pod unit tracks the location of the individual and transmits the location to the central monitoring system. The pod unit includes a triaxial accelerometer for gathering acceleration data for transmission of the data to the central monitoring station for analysis at a later time.

Abstract: A method for remotely monitoring the activities of a minor or dependent child or adult, on command from a parent unit. The child unit contains a sensitive audio microphone to provide the holder of the parent unit the capability to periodically listen to activity in close proximity of the child unit, thereby offering the holder of the parent unit a measure of confidence in the state of well-being of the holder of the child unit. The preferred embodiment provides a means to transmit an alert signal from the child unit to the parent unit in the event of an emergency. The transmission media used to interconnect both units is wireless, and may comprise radio frequency or infrared optical means, or any combination thereof.

Abstract: Structure for controlling the output power from a microwave transmitter uses a digital value transmitted under control of software to an outdoor unit of a transmitter thereby to allow the power output of the transmitter to be changed under control of the software. The digital value is generated by an indoor unit of the transmitter or a remote transmitter across a link or elsewhere in a network. Other parameters of the transmitter can also be varied under control of the software. These parameters include the frequency and muting as well as the generation of test signals at the transmitter. In one embodiment, the outdoor unit contains a non-volatile memory in which the digital value is stored and a microprocessor which generates a control signal from the digital value to set the output power of the transmitter. Software executed by the microprocessor can correct the control signal for temperature so that the output power of the transmitter does not change when outdoor temperature changes.

Abstract: In a freight tracking and routing system, each individual package is provided with a tag physically attached thereto. The tag includes a radio or infrared transceiver, and a microprocessor. At important nodes at geographical locations within the distribution system, location transceivers broadcast signals representative of their locations. The microprocessor, in response to receiving a desired destination signal, emits a signal commanding external equipment to take the package so that it remains at the desired location. The tags are also capable of being electronically queried, or alternately can emit distress signals when they do not reach a particular location at a particular time.

Abstract: A dynamic power consumption reduction apparatus for reducing power consumption by temporarily delaying multiple data transfer interfaces. Data transfer interfaces are only delayed in rare circumstances where an exceptionally high number of data transfers are occurring for a period of time. The number of active data transfer interfaces is monitored, and a count value is incremented or decremented depending on the number of active data transfer interfaces. If the count value reaches a threshold value, it indicates that the number of data transfers for a predetermined period of time is exceptionally high, and therefore power consumption is high. Where the number of data transfers is high for a predetermined period of time, delays are injected into the handshake cycle to delay return of data acknowledge signals from data receivers to data transmitters. The delays are discontinued when the data transfer interface activity is reduced to a normal level.

Abstract: A radio communication apparatus which is charged by a charge table comprises a connection unit to connect another communication apparatus, a radio communication unit to communicate a communication signal of another communication apparatus through a radio line, and a control unit to finish or continue the communication by the radio communication unit in accordance with whether another communication apparatus has been connected to the connection unit or not when the apparatus is connected to the charge table.

Abstract: A communications system includes at least two communications units, each communication unit including a transmitter capable of transmitting to the other unit on one or more frequencies, under the control of a mode control unit and wherein acquisition or a locking of frequencies of the two communications units and timing signal recovery is achieved by transmitting signals on a group of predetermined frequencies, the transmission on each frequency being for a predetermined time frame in a sequence which is repeated after n+1 time frames, wherein n is the number of different frequencies to be transmitted by the originating communications unit, and the receiving unit including a receiver operating on one of the predetermined frequencies for n+1 time frames until the receiving unit receives a signal from the originating unit and transmits an acknowledgment signal to the originating unit thus locking the two units on one of the predetermined frequencies such that information, transmission and reception can proceed

Abstract: A transmission power control method of a mobile station in a CDMA (Code Division Multiple Access) system which primarily controls transmission power of the mobile station by using a closed loop control which enables high accuracy power control. When the received power at the base station of a signal from the mobile station suddenly increases owing to the state of buildings surrounding the mobile station, the transmission power of the mobile station must be quickly reduced to prevent the interference to other mobile stations. The mobile station measures an average value of the received power per transmission power control period of a desired signal from the base station, and detects the difference .DELTA.RSSI between the current average value and that of one of the previous transmission power control periods. If .DELTA.RSSI exceeds a reference power difference .DELTA.P.sub.th, transmission power P.sub.T corresponding to .DELTA.

Abstract: A communication system has a base station having memory for storing information within a plurality of information files relating to a plurality of information services. A receiver receives an information service request for requesting information within at least one of the plurality of information files from a selective call receiver. A transmitter transmits the information requested from within the at least one information service file to the selective call receiver. The selective call receiver includes a generator for generating the information service request and a transmitter transmitting the information service request. The selective call receiver receives the information transmitted from the base station in response to the information service request and a display displays the received information.

Abstract: A method of controlling an external radio frequency amplifier of a radio telephone and a control system therefore. The power amplifier of the transmission side of the radio frequency amplifier is controlled to turn on and off, on the basis of at least one control signal (BENA1, BENA2) entering the radio frequency amplifier separate from a signal to be transmitted from the radio telephone. The control signal (BENA1, BENA2) contains information about the starting and ending instant of transmission.

Abstract: A base station (102) automatically remotes to a speakerphone mode of operation and connects an incoming call while an external electronic device (104) is simultaneously controlled.

Abstract: A portable transceiver and an ESN transfer system for a car telephone system. The ESN and the MSN, which are manufacturer-controlled numbers, are stored in an EEPROM mounted on the panel of the portable transceiver. When the panel on which the EEPROM is mounted is to be replaced, only the ESN is transferred to the EEPROM of the new panel. Upon completion of the ESN transfer, the ESN in the EEPROM of the replaced panel is rewritten to data, which would make its specific part, such as the manufacturer's ID number, to be judged "incorrect". No ESN whose specific part is "incorrect" can be transferred. The ESN transfer unit, connected to a connector provided in the casing of the portable transceiver, performs said ESN transfer.

Abstract: A transceiver having a transmitting unit and a receiving unit for performing substantially simultaneous communication with another transceiver in both directions by using a single frequency carrier. The transceiver includes a unit for generating a synchronizing signal for alternately switching between a transmission time period and a reception time period of the transceiver at a predetermined period, a signal processing unit for converting an input signal into a compressed signal by compressing a time axis of the input signal by a predetermined ratio, and affixing the synchronizing signal to the compressed signal, a unit for supplying the compressed signal with the synchronizing signal to the transmitting unit during the transmission time period, and a unit for reproducing an original signal from a signal transmitted from the other transceiver and received by the receiving unit during the reception time period, by expanding a time axis of the signal by a predetermined ratio.

Abstract: A method is provided for autonomous radio talk group configuration among radio transceivers. The radio transceivers are placed in a group configuration mode that operates on a communication channel (310, 320). A configuration master transceiver is selected and the other transceivers designated as configuration slave transceivers (330). The configuration master transceiver transmits radio talk group identification information on the communication channel, and the configuration slave transceivers receive and store this radio talk group identification information for use in radio talk group communications (340).

Abstract: A method and structure for increasing the security of a cordless telephone system by automatically altering the security code information stored in the cordless telephone handset and base unit. Thus, without requiring effort on the part of the user, the security codes are updated to differ from the previous security code setting, while always maintaining corresponding security codes in the handset and base unit. In one embodiment, the updating of the security code is performed at any convenient time interval or in response to any convenient activity, such as the placement of the handset into the base unit for storage and recharging. In one embodiment when the security code is to be updated a new security code is generated in a predetermined manner, for example by random number generation, by the handset.

Abstract: In an exemplary embodiment, a base station maintains RF communication with mobile units using a polling protocol which may communicate at a higher or lower data rate, depending on the channel conditions. The base station transmits a general polling message at the lower data rate, and, associated therewith, transmits a test pattern for evaluation by the mobile units. Upon receipt of the transmissions, the mobile units analyze the test pattern to determine whether communication at the higher data rate is possible. Based on the determination, the mobile units select the appropriate rate to transmit data messages. The test pattern can be associated with a query from a mobile unit having a message to send, or with a contention polling message from the base.

Abstract: In personal communications systems, a wireless handset user is not generally aware of the quality of the radio link to the base station when a call is in progress. Novel mechanisms are disclosed by which the handset user is given up-to-date information concerning radio link parameters. According to the invention, the base station continuously analyzes the received signal of a handset and sends back to the handset a signal indicative of the link parameters. Upon receiving the signal, the handset informs the user by way of either processed sidetone or other indications.

Abstract: Base Station Transceiver Equipment 10 is provided such as for use in a cellular radio telephone system. In a first aspect of the invention, a device within the equipment measures a parameter (e.g. timing, signal strength) of a mobile transceiver and instructs the mobile to adjust that parameter of its transmitted signals. Subsidiary transceiver equipment 11 (a diagnostic sub-system or "test mobile") is provided in relative proximity to the base station transceiver equipment. The subsidiary equipment can change the parameter of its transmissions to simulate relative distance from the base station transceiver equipment for test purposes. In other aspects of the invention, a device is provided for testing the base station antenna.

Abstract: In a wireless LAN packet communication system, for each successfully received packet the strength of the received signal is measured at a target node by monitoring an A/D converted rssi (received signal strength indication) signal. A record of minimum strength among successfully received packets is maintained at the target node. For each succesfully received packet the difference between the signal strength of the packet and the recorded minimum is calculated at the target node and sent over the link to the source node as a quantitative difference indicator. The source node maintains a moving average of difference indicators received over time and adjusts the transmitter power level so as to maintain the moving average at a preselected link margin threshold level. Alternatively, the calculation of a desired source node power level change is performed at the target node and transmitted to the source node.

Abstract: An adaptive power control used on a radio network and a method for adaptively controlling the transmit power level of member stations on the network. An exemplary network (12) includes a plurality of member stations (10a through 10f) between which radio signal propagation conditions are subject to change. Each member station includes a transceiver (21) having a transmitter (26) and a receiver (28) section. The transmit power level of the transmitter is controlled by a variable gain circuit (48) in response to a variable gain signal produced by a control (34). A member station uses a transmit power level determined by reference to a database in which signal-to-noise ratio (SNR) data defining the quality of each communication link and the transmit power levels last used for communication between each pair of member stations of the network are stored.

Abstract: The process and apparatus of the present invention limits the output power of a radiotelephone, operating in a cellular system in the preferred embodiment. This ensures the transmitted sidebands and synthesizer phase noise remains within a certain specification. This is accomplished by power detection and a correction accumulator that together generate a gain control signal by limiting the gain adjustment to a maximum value, even when the cell site communicating with the radiotelephone is sending power turn-up commands to the radiotelephone. This process includes dynamically correcting the output level of the transmitter due to gain variations in the transmitter stages or gain control elements.

Abstract: A method and apparatus for implementing a protocol for controlling transmitter power in a wireless LAN. The LAN is assumed to include a number of nodes, each node including a transmitter and a receiver for communicating information between computers located at the node. To initiate the protocol, the transmitter of a data sending node first transmits a signal including a transmitter power signal to each of the receivers of the data receiving noes. The information contained in the transmitter power signal may be transmitted in one of the fields of the data packet of the signal. The receivers of the data receiving nodes individually transmit power control feedback signals back to the transmitter of the data sending node. Information in each of the power control feedback signals may occupy a field in the data packet transmitted from the receiver to the transmitter of the data sending node.

Abstract: A method and apparatus for closed loop frequency control in a two-way radio communication system (100) include a base communication unit (104) and a portable communication unit (108) having a portable-to-base initiation channel (202) assigned to a predetermined frequency. A signal is transmitted (502) from the portable communication unit (108) to the base communication unit (104) on an initiation frequency of approximately the predetermined frequency. The base communication unit (104) determines (506) from the signal a frequency correction factor (326) for recalibrating the initiation frequency in accordance with the predetermined frequency. The frequency correction factor (326) is communicated (512) to the portable communication unit (108), and the portable communication unit (108) recalibrates (516) the initiation frequency in response.

Abstract: In cordless telephone sets comprising at least one base station and at least one handset, an exchange of identification codes takes place between the base station and the handset. In order to realise greater flexibility with cordless telephone sets, the invention proposes to establish a connection between the handset and the base station also by means of a second identification code stored in the base station. In this manner, any user without knowing the identification codes to be exchanged between the handset and the base station can sign on and sign off a handset at any compatible base station, provided that he knows the second identification code.

Abstract: A method (200) and apparatus (100)is provided for a radio having adjustable operating parameters to adjust at least one such adjustable operating parameter based on the current location of the radio. Operating parameters which may be so adjusted include, but are not limited to, the following: transmitting power, operating channel, operating band, modulation type, modulation index, frequency deviation, squelch setting, channel spacing, control channel (for trunked communications), noise blanker characteristic, and receive bandwidth. In another embodiment, transmissions by the radio can be inhibited as a function of the location when it is determined that the location is within a hazard area.

Abstract: The remote instrument reading and telemetry system of the present invention includes at least one instrument link interconnected to a data gathering device and a remote station interrogation apparatus. The interrogation apparatus and instrument link both include radio transmitters and receivers so information and instructions can be communicated between them. In the interrogation mode, the interrogation apparatus instructs the instrument link to transmit information (e.g., data from the data gathering device) in a specified manner, within certain time frames, and in a specific frequency channel. Before requesting the transmission of information, the interrogation apparatus determines which of the available reply radio channels is the best for transmission of information and instructs the instrument link to use this reply channel.

Abstract: A mobile test set for testing a mobile-radio system containing system components to be tested and at least one operation and maintenance center. The mobile test set has a first interface for the exchange of test signals between the mobile test set and at least one of the system components and a second interface for the exchange of control signals between the mobile test set and at least one man-machine interface. The two interfaces are linked so that the exchange of the control signals takes place via at least one of the system components between the mobile test set and at least one man-machine interface installed in the operation and maintenance center.

Abstract: The present disclosure includes a discussion of a data transfer system. The data transfer system is responsible for transferring data to and from a radio transceiver (107) and all the corresponding peripheral device ( 111, 113 ) contained in within the radiotelephone (103). The data transfer system includes a data bus (109), a master controller within the transceiver (107) and a peripheral controller within each of the peripheral devices. The data transfer system has an initialization state and a operational state. During the initialization state the data bus (109) operates at a lower frequency than during the operational state. The lower speed increases the time allowed for the assignment of the unique addresses for each of the peripheral controllers. Upon detecting completion of the initialization state, the master controller conducts the change to the operational state.

Abstract: A networked radio communication system for transmitting a radio signal between a source transceiver and a plurality of destination transceivers. The source transceiver first transmits an interrogate signal that includes a synchronize code and an address code that is indicative of a particular destination transceiver. If the particular destination transceiver receives the interrogate signal, an acknowledge signal that includes the address of the destination transceiver that is transmitting the acknowledge signal is transmitted back to the source transceiver. The source transceiver compares the address included in the interrogate signal with the address included in the received acknowledge signal and determines if a communications link is established. If a communication link is established, a feedback signal is provided to the operator of a source transceiver indicating that the source transceiver is in communication with the particular destination transceiver.

Abstract: Apparatus operable with different cellular telephone systems and signalling protocols is described. Signalling messages, both data messages and supervisory related signals between a cellular telephone microcontroller (4) and a base station are transferred via a baseband signalling circuit (10). The baseband signalling circuit is operable to employ different signalling protocols, the protocol being selected by control bits provided from the microcontroller to the signalling circuit. In a preferred embodiment, the signalling protocol selection is made between an AMPS/TACS signalling protocol and a NAMPS/NTACS subaudible signalling protocol.

Abstract: A LAN or other data network includes at least first and second repeater units for receiving data signals and repeating them to other parts of the data network and a transceiver unit for transmitting and receiving data which is connected to the first repeater unit by a primary data link and to the second repeater unit by a secondary data link. The primary data link comprises a primary transmit line for transmitting data from the transceiver unit to the first repeater unit and a primary receive line for receiving data from the first repeater unit and transmitting it to the transceiver unit; and the secondary data link comprising a secondary transmit line for transmitting data to the second repeater unit and a secondary receive line for receiving data from the second repeater unit and transmitting it to the transceiver unit.

Abstract: In order to provide for a mobile communication network of a cellular type a transmission power control system capable of keeping a signal quality constant, an average bit error rate y is measured on a receiving side in connection with a communication channel being in use (step 100). If the average bit error rate y is not greater than a first rate threshold value LV1, transmission power is decreased by a predetermined amount on a transmitting side (step 102). If the average bit error rate y is not less than a second rate threshold value LV2 which is greater than the first rate threshold value LV1 (step 103), the transmission power is increased by the predetermined amount on the transmitting side (step 104). Preferably, an average reception level is additionally measured to adjust the transmission power when the bit error rate is less or greater than the first or the second rate threshold value.

Abstract: A portable communication device (10) is controlled by voice recognition circuitry (20) remote from the portable communication device. The portable communication device includes apparatus for producing and transmitting a parametric representation of voice commands. The remote circuitry (which could possibly be a base station, a mobile repeater, or simply a dedicated box, separate from the portable) produces control signals, responsive to the parametric representation of voice commands, for controlling the portable communication device.

Abstract: A multi-user radio system, such as a trunked radio system has sets of operations ("storm plans") for execution in emergency situations. A central control and management processor is arranged to define a list of users (20) associated with a respective storm plan and to permit the defined users to execute the respective storm plan.

Abstract: An HF radio transceiving apparatus that maintains communication integrity by employing a plurality of receivers, each capable of operating in separate and independent communication modes. One embodiment of the apparatus includes an antenna, a programmed controller having a plurality of control signals, first and second receivers and a transmitter section. The receivers receive and demodulate radio signals transmitted from external radios in common or mutually exclusive communication modes, and provide link-data information to the programmed controller. The transmitter, responsive to the programmed controller and coupled to the antenna, transmits modulated data in one of the common or mutually exclusive communication modes.

Abstract: A wireless transmission system includes a plurality of terminal units, a specific one of which is provided with a transmission/receiving circuit that transmits a reference signal of a local oscillation frequency, while all others of which are provided respectively with a transmission/receiving circuit that prepares, on the basis of the reference signal received, a local oscillation frequency signal for frequency conversion of transmitting/receiving frequency signal and intermediate frequency signal, to thereby realize the system at lower costs even when a high local oscillation frequency is employed.

Abstract: A method for the contactless transmission of information between a transmitter/receiver unit and a transponder.

Abstract: A mobile telephone usable both as a portable and as an installed telephone, capable of saving battery power when used as a portable telephone, and safely starting up voice-dialing when used as an installed telephone. Discriminating circuit (3, 3A, 14) discriminates which use the telephone is now in, portable or installed. In the former use, start-up circuit (7, 15) is manually activated to supply power from battery pack (1) to voice-dialing unit (8). The power supply is cut off in response to reset signal R supplied from the voice-dialing unit when voice-dialing ends. In the latter use, voice-dialing unit is kept switched on to the vehicle battery and ready for start-up in response to voice input.

Abstract: A telephone system in which communication between fixedly sited primary stations and transportable secondary stations is by way of respective time division duplex (TDD) radio links, particularly single frequency TDD links. In order to reduce radio interference between closely sited primary stations, their transmit periods are frame synchronized by using an externally produced radio signal. Conveniently a broadcast television field synchronization signal can be used.

Abstract: A communication system in which a plurality of multipoint connected satellite stations are connected via down line and an up line to a master station. Each of the satellite stations monitors presence or absence of occurrence of an abnormality in the down line, judges whether the abnormality is present or not and, where the abnormality is present, informs the master station of the nature of the abnormality via the up line. In turn, the master station monitors presence or absence of an alarm indicating abnormality from each of the satellite stations, judges whether the alarm is detected or not and, where the alarm is detected, reads past record information concerning abnormality detection in the satellite station concerned and information on retraining execution time, then judges whether the down line is normal or not and, where the down line is normal, sends a training signal again to the down line to retrain a MODEM corresponding to the satellite station concerned.

Abstract: A communication device (10) comprises a coupler (19) for coupling an external device (30) to the communication device, and controller (16) for controlling the communication device., The controller has at least first and second terminals (22 and 23) for receiving digital numbers from the external device, each digital number representing a mode of operation for the communication device. The controller also includes an apparatus for transmitting a test pulse to the external device, and an apparatus for receiving a response pulse in response to the test pulse. The response pulse has predetermined direction, duration and polarity indicating a mode of operation for the communication device.

Abstract: A method and apparatus are provided for synchronizing over-the-air time division duplexing communication within a defined geographical coverage area (201) of a communication system (200) that provides at least cordless radiotelephone operation between a plurality of portable radiotelephone transceivers and a plurality of telepoint base stations (202, 204, 206) geographically located within the coverage area (201). The communication system (200) transmits over-the-air a synchronization timing signal (203) including timing information corresponding to a transmit-and-receive duty cycle timing for time division duplexing communication. At least one telepoint base station (204, 206) within the coverage area (201) receives the synchronization timing signal (203). The at least one telepoint base station (204, 206) synchronizes its over-the-air time division duplexing communication transmit-and-receive duty cycle timing to the timing information.

Abstract: A device for the bi-directional transmission of data between a master system and a slave system uses a single transmission antenna and a single reception antenna each tuned to the same frequency; the master system comprises first data transmission circuits for transmitting first data to the slave system by modulating an electromagnetic signal at the frequency; detection circuits for detecting, during the transmission of the electromagnetic signal, variations in electrical characteristics of the master system induced by a modulation of the impedance of the slave system as a function of second data to be transmitted from the slave system to the master system; and restoring circuits for restoring the second data on the basis of the detected variations; and the slave system comprises reception circuits connected to the reception antenna for restoring the first data; a rectifier circuit connected across the reception antenna for rectifying an electrical signal induced in the reception antenna by the electromagneti

Abstract: The problem of noise enhancement is eliminated in communications systems by predistorting the amplitude of the transmitted information signal in a manner which compensates for the amplitude distortion introduced in a portion of the communications channel. In the disclosed embodiments, the communications system includes two signal transceivers which communicate with one another through a communications channel. The communications channel includes two-wire subscriber loops adjacent to each signal transceiver with a four-wire transmission path disposed between the subscriber loops. Each transceiver transmits an information signal which, depending on the system noise characteristics, is predistorted to compensate for all or a portion of the amplitude distortion introduced in a subscriber loop adjacent to that signal transceiver. The predistortion necessary to provide such compensation is determined at each transceiver in response to received signals at that transceiver.

Abstract: A signal reproducing apparatus operating on a wireless basis and having a status signal multiplexed with audio signals and transmitted to a receiver containing a display, the status signal indicating the current operating status of a recording medium player. On receiving the status signal, the display indicates the current operating status of the recording medium player so that the user may accordingly control the player from a distance without the intervention of wires.