Abstract: The present invention relates to a radio communication apparatus for transmitting and receiving signals according to a modulation technique using the so-called flipper, and more particularly to a radio communication apparatus which can detect a flipper data element in a received signal, with simple configuration in the receiver's side. The invention further relates to a radio communication apparatus which can efficiently execute verification of an ID code also in the transmitter side, for instance, by verifying the ID code by checking for the flipper data element to determine whether it is included.

Abstract: A switch having two planes opposing and substantially in parallel to each other and switching between a first electrode and another electrode by pressing down one of the planes. Contact point patterns each made of a conductive material having a specified shape are provided on one of the planes. Stripe electrode patterns in which the first electrode and the other electrode are alternately positioned are provided on the other plane in a region where the contact pattern on the one plane is superimposed when that plane is pressed down.

Abstract: A cordless telephone can include a base unit including a cordless telephone circuit, a power source circuit and a resistor connected between a pair of power output terminals of the power source circuit, and a handset unit including a cordless telephone circuit, a secondary battery, a circuit connected between a charging terminal which receives power supply output from the power source circuit and a terminal of the secondary battery and consisting of a diode and a resistor connected in parallel to each other and a power break detection circuit. The secondary battery is usually charged by power supply from the power source circuit via the charging terminal and diode when the handset unit is placed in a cradle of the base unit, and electric power is supplied from the secondary battery to the cordless telephone circuit in the handset unit to operate in intermittent reception mode.

Abstract: An antenna device for a radio transmission-reception apparatus is disclosed which comprises an antenna element which is to be electrically and mechanically connected to a printed-circuit board fixed in a housing of the radio transmission-reception apparatus, an inverted U-shaped hollow reinforcement spacer, an antenna cover and a retaining portion formed on the housing. The reinforcement spacer has a hole formed in the top portion thereof a diameter of which is substantially equal to that of the antenna element to slide therethrough, a slit formed continuously from the hole to a base end thereof through which said antenna element can be entered in the reinforcement spacer, and a flange formed around the outer circumference of the base end. The antenna cover is constituted to accommodate therein the antenna element with the reinforcement spacer, and has a flange formed around the circumference of a base end thereof.

Abstract: A device for connecting an external sound generator having a plug and being incorporated in an apparatus having a circuit outputting an electrical sound signal. The external sound generator is, for instance, either one of a headphone having the plug of 3-pole stereophonic type or a earphone having the plug of 2-pole monophonic type. The device comprises a single jack having a first and second plus contacts and a minus contact for receiving the electrical sound signal from the outputting circuit through the first plus contact and for supplying the electrical sound signal to the plug connected to the jack and an impedance element, such as a electric resistor, connected between the first and second plus contacts. The impedance element prevents a short circuit for use of an earphone having a 2-pole monophonic plug.

Abstract: A method and two-way radio apparatus are disclosed which provide for the storage and recollection of call history information, in a call history memory, based on a system ID codes and group ID codes which are linked to receive ID codes and transmit ID codes in an ID code memory. The call history memory may be arranges as a FIFO queue, and calls may be automatically replied to upon reviewing the contents of the call history memory.

Abstract: Radio equipment based on an AFC system comprising a local oscillator, a reference frequency oscillator, a receiver, a frequency comparator, an AFC controller, a temperature detection sensor, and a memory. The AFC controller inputting, when starting AFC, reads out a control frequency corresponding to the detected temperature inputted thereinto to control the reference frequency for the reference frequency oscillator. When a lock signal is inputted thereinto, the detected temperature and control frequency are stored in a memory.

Abstract: A land mobile radio communication system has a plurality of cell sites, each of which typically has a plurality of repeaters. The over-the-air radio communications between the cell site repeaters and the mobile radios in the system include both a voice component and a data component. The data component is carried as low-frequency subaudible information. Communication channels are provided between the radio users at each site as well as between users at different sites and between mobile radio users and the public telephone network. Within a cell site, the transmitted and received communications are digitized and passed through serial buses in a time multiplex fashion. The digitized voice is transferred between time slots to provide the required switching function. The system includes operational software to provide direct inward dial telephone number recognition, automatic voice prompts for a user entering a new cell, call priority override, fraud control for radio fleets and a dynamic control channel.

Abstract: In a DC offset circuit for a Cartesian loop, a DSP supplies step by step a slope voltage from a minimum DC output voltage, up to a maximum DC output voltage, to input sections of operational amplifiers for modulation. This arises each time transmission is started in a state where a signal Q' and a signal I', each based on only a carrier wave, are outputted from a quadrature demodulator. When comparators detect that output from operational amplifiers is 0 V, the DSP decides a value of the slope voltage then as a DC offset voltage value. Operation is started centering on this DC offset voltage value.

Abstract: A land mobile radio communication system has a plurality of cell sites, each of which typically has a plurality of repeaters. The over-the-air radio communications between the cell site repeaters and the mobile radios in the system include both a voice component and a data component. The data component is carried as low-frequency subaudible information. Communication channels are provided between the radio users at each site as well as between users at different sites and between mobile radio users and the public telephone network. Within a cell site, the transmitted and received communicatios are digitized and passed through serial buses in a time multiplex fashion. The digitized voice is transferred between time slots to provide the required switching function. The system includes operational software to provide direct inward dial telephone number recognition, automatic voice prompts for a user entering a new cell, call priority override, fraud control for radio fleets and a dynamic control channel.

Abstract: A method and apparatus for placing calls in a multi-system land mobile radio network. A plurality of call destinations are linked or grouped together into a call group. Each call destination has a preferred system. Selection of a first call destination points to or is linked to at least a second call destination. If the preferred system for a current call destination is not accessible, then a second call destination, selected in accordance with the first call destination is made the current call destination. Selecting a call group causes a radio to attempt a plurality of call destinations, each in sequence, until an accessible preferred system is found, indicating that the current call destination is valid. If an accessible system is found, then the call is placed thereto.

Abstract: A radio communication apparatus comprises a first/second modulator for modulating a first/second signal according to a first/second frequency, a first demodulator for detecting the received first modulation signal and regenerating the carrier, a clock regenerator for regenerating a clock from the detection output from the first demodulator, an amplitude sampler for sampling the amplitude of the received first modulation signal according to the regenerated clock, a second demodulator for controlling the frequency of the received second modulation signal and executing demodulation for the signal, and a gain controller for executing gain control for the output from the second demodulator according to the output from the amplitude sampler.

Abstract: A novel battery case for a portable terminal unit includes a first battery storage case monolithically integrated with the basic body of the portable terminal unit for accommodating two batteries within an opening thereof, the batteries being arrayed in parallel in one step. A second battery storage case in which two batteries can be set within an opening thereof, the batteries being arrayed in parallel in a separate step, is also provided. The second storage case can be mounted onto the basic body of the portable terminal unit so that the opening of the first battery storage case will be opposite to the opening of the second battery storage case.

Abstract: An analog/digital receiver comprises a noise detecting circuit for checking whether a noise component, output from an analog signal detecting means, is not less than a specified value, and an RSSI detecting circuit for checking whether received signal strength, output from the receiver, is not less than a specified value. A discriminating circuit is included for making a determination as to whether the received input is an analog modulation signal or a digital modulation signal according to the result of the determination made by the noise detecting circuit as well as by the RSSI detecting circuit. A select switch selects the output from either the digital signal detecting circuit or the analog signal detecting circuit.

Abstract: A receiver converts an echo received by a transducer to a supersonic echo signal, and a controller measures the depth of obstacles depending on a timing for receiving the supersonic echo signal, obtains an echo level according to quantity of the supersonic echo signal, and determines the condition of the bottom depending on echo levels of a series of supersonic echo signals. A display unit provides a result of detection at a position of corresponding depth scale on a first display area for providing graphic displays of the obstacles as well as the bottom with a depth scale with a gradation or a pattern type corresponding to the echo level. Graphic displays of the echo level are also provided at a position corresponding to depth on a second display area having graphic displays corresponding to depth scale in the first display area.

Abstract: To make it possible to easily carry out registration of a mutual ID number (ID) in a slave telephone set in cordless telephone device by only operating a switch or buttons, in the cordless telephone device according to the present invention, a sound generating element and a sound receiving element located closer and opposing to each other when the slave telephone set is set on a cradle of the master telephone set are provided in the master telephone set and the slave telephone set respectively, and ID signal sound is transferred between the two elements, so that even an ordinary user can carry out the ID registration requiring very complicated operations in the conventional technology without fail.

Abstract: A speed detecting apparatus mounted on an object moving on the ground detects a Doppler frequency for computing a moving speed thereof by receiving reflection waves of a microwave signal or a millimeter wave transmitted to the ground. The apparatus comprises a plurality of transmitting/receiving systems each having an antenna and a transmitter/receiver, and a signal processing section for computing moving speed according to Doppler frequency detected by the transmitting/receiving systems. Directivity of an antenna provided in each of the plurality of transmitting/receiving systems is set at a different angle respectively.

Abstract: In a scanning receiver for receiving a signal by scanning the frequency of a received signal, the speed of a scanning operation is made fast with skipping non-modulated signals and digital signals. AF signal is changed into A/D converted values, and first and second amplitude distribution are respectively formed from A/D converted values. Non-modulated signal is discriminated based on the first amplitude distribution, and digital signal is discriminated based on the second amplitude distribution.

Abstract: The cordless telephone system according to the present invention comprises a synchronization inhibiting circuitry for inhibiting, when a calling station sends a communication end request code, synchronization with a called station in communication therewith for a prespecified inhibit time after transmission of the communication end request code, and a communication terminating circuitry for terminating communication if a state where synchronism with the called station is lost continues for a prespecified reference time during communication. Thus, communication is terminated without fail when a call ends, and transactions of unnecessary electric waves are reduced.

Abstract: A controller shifts the frequency of the local oscillator with a frequency shift circuit so that as many channels to be scanned as possible will be included within specified bandwidths, detects a desired received signal by scanning each of the specified bandwidths with the shifted frequency, scans each channel within the bandwidth where the desired received signal was detected, and changes the frequency of the local oscillator or shifts the frequency of the local oscillator with the frequency shift circuit so that the desired channel frequency identified above will be at the center of said bandwidth.