Abstract: A digital radio transceiver integrated circuit includes MOS transistors with normal threshold voltages in the digital circuits, and with reduced threshold voltages in at least some of the analog RF components. This allows the transceiver to be reduced in size and weight, without requiring performance to be compromised.

Abstract: Disclosed herein is a wireless repeating apparatus for mobile communication system. The present invention relates generally to a wireless repeating apparatus for repeating a signal at the same frequency as that of a wirelessly received signal in a mobile communication system. The present invention relates more particularly to a wireless repeating apparatus for mobile communication, which detects an amplitude and a phase of a wirelessly received signal and synthesizes the detected results to generate inverse phases in multiple stages, thus enabling interference signals to be eliminated, and enabling the repeating apparatus to be used over a open area using the elimination of the interference signals.

Abstract: Wireless communications equipment that wirelessly communicates signals on a plurality of communication frequencies includes: a baseband frequency-side frequency conversion means that performs conversion between baseband signals on the baseband frequency and signals on a stipulated frequency higher than the baseband frequency and different from the intermediate frequency, an intermediate frequency-side frequency conversion means that performs conversion between the signals on said stipulated frequency and intermediate frequency signals on a plurality of intermediate frequencies corresponding to a plurality of communication frequencies, and an unwanted frequency signal component removal means that removes signal components of unwanted frequencies from the signals on said stipulated frequency.

Abstract: A method and apparatus for reducing power consumption of a mobile communication terminal operated at a slotted mode in a spread spectrum communication system such as a CDMA cellular mobile communication system. The mobile communication terminal reduces a paging channel monitoring time by entering a sleep mode or a wake-up mode at an arbitrary timing instead of a PN code rollover period, resulting in the increment of a standby time of the terminal.

Abstract: The present invention relates to improvement of even order distortion noise, DC offset, and non-linearity of mixer circuits. According to the present invention, a mixer circuit is provided, which comprises a splitter for splitting an input signal to the first and second signal having phase difference of 180 degree, a local oscillator, first mixer for mixing the first signal with the local oscillation signal, second mixer for mixing the second signal with the local oscillation signal, and subtractor for subtracting the output of the second mixer from the output of the first mixer.

Abstract: A switching amplifier generates noise at its switching frequency and harmonics thereof. The noise at these harmonics, for an audio amplifier, will be generated with significant amplitude in the AM band. Thus, an AM tuner will experience interference problems if the tuner frequency is sufficiently close to one of these harmonics. To avoid this problem the switching frequency of the switching amplifier is chosen based on the tuner frequency. Thus, the switching frequency is chosen to avoid having harmonics at or too near the chosen tuner frequency. The switching amplifier is disabled when the tuner is in seek or scan mode. Instead of using the tuner frequency to determine what switching frequency should be used to avoid interference, the interference can be detected directly to cause a change in the switching frequency and thus remove the interference.

Abstract: The disclosed invention provides a wireless communication receiver that is able to lessen the effect of noise that accompanies gain change by programmable gain amplifiers. Such noise is produced when direct conversion type programmable gain amplifiers by which gains are adjustable in steps are used for gain control of signals of CDMA or the like in which reception is not intermitted.

Abstract: An integrated circuit superheterodyne radio receiver includes a notch filter coupled with an amplifier for amplifying radio frequency (RF) signals to improve image signal rejection. The notch filter includes a first oscillator circuit with a tank circuit having a resonant frequency corresponding to the unwanted image frequency signal. A control circuit includes a second oscillator circuit, a master bias circuit and a slave bias circuit. The second oscillator circuit is substantially similar to the first oscillator circuit. The master bias circuit is responsive to an amplitude of oscillatory signals in the second oscillator circuit for limiting a flow operating current such that the second oscillator circuit is restrained to operate in a marginally oscillatory state. A slave bias circuit is responsive to the master bias circuit for similarly limiting a flow of current, for operating the first oscillator circuit.

Abstract: A radio back-end circuit that includes an integrator and a first variable voltage translator having a signal input coupled to the output of the integrator circuit. Also included is a first variable low pass filter, a second variable voltage translator, and a variable attenuator. These components of the radio back-end circuit are communicatively coupled such that noise is reduced in radio communications and signal and reception range control is improved in certain situations.

Abstract: A transmit-receive switching circuit of a wireless communication system comprises a selecting portion for switching the communication system in a waiting mode into a master; a controller for determining a transmit-receive frequency according to the operating of the selecting portion and generating a control signal; a band selecting portion for selecting an inputting signal of an upper band or a lower band of a receiving signal passed through an antenna and a duplexer according to the control signal of the controller; a first switching portion for selecting an upper band pass filter and a lower band pass filter that are operated by the band selecting portion; an amplifying portion for amplifying a receive signal passing through the switching portion; a second switching portion for switching the receive signal amplified at the amplifying portion according to the operating signal of the band selecting portion and determining to be supplied to an upper band filter or a low band pass filter of a second filtering p

Abstract: A radio communication device (100) such as a mobile telephone comprises signal converters (110, 130, 140), a band-pass filter unit (120) and an oscillator (150). In the receiving mode (I) a first converter (110) converts an HF signal into an intermediate ZF signal (20) which, upon filtering by the band-pass filter unit (120), is converted into an NF signal by means of a second converter (130). In the transmission mode (II), the device (100) employs the first converter (110) and the filter (120) for compression of the dynamic range of a microphone signal (40). The first converter (110) converts the microphone signal (40) into a further intermediate ZF signal (50) which is subjected to amplitude limitation by means of a limiter circuit (121) in the filter unit (120) and filtered by means of a filter (122). The third converter (140) converts the filtered and limited signal (51, 52) again into a low-frequency signal (60).

Abstract: A frequency converter including a mixer circuit which inputs a local oscillation signal and a radio-frequency input signal modulated for communication of information, and performs frequency conversion. A buffer amplifier is higher than a desired signal frequency band, and has a low-pass passage characteristic of cut-off frequency lower than an adjacent channel carrier frequency.

Abstract: An auto-adapt circuit (200) for altering radio receiver parameters due to demodulator transients and preventing the loss of received information. The auto-adapt circuit includes a detector circuit (215) connected to the output of a receiver demodulator (203) and a switch (219) controlled by the detector circuit (215). The detector circuit (215) detects a transient voltage at an upper threshold limit or at a lower threshold limit such that a transient at an output of the receiver demodulator will actuate the at least one switch for varying demodulator coupling parameters of the radio receiver.

Abstract: An analog circuit for receiving satellite signals through an antenna. The circuit includes frequency transposition circuits and an analog/digital converter. Each frequency transposition circuit includes at least two frequency dividers of which due first is programmable so as to provide division ratios 140 and 143. The other divider provides one of the division ratios of 10 or 11. A third divider provides ratios of 3, 5, 7 or 8. These division ratios enable a single analog integrated circuit topography to allow a large number of possible applications including civil or military receivers operating on the GPS constellation or on the GLONASS constellation.

Abstract: A circuit for automatically discriminating audio intermediate frequencies of a received television signal that has a simple, compact and inexpensive circuit structure and can operate stably.

Abstract: A mobile communication system comprising an analog baseband processor that is configured for providing improved DC offset compensation. An offset compensation circuit of the analog baseband processor generates a first DC offset compensation signal to preset DC offset voltage of analog baseband signal when the mobile communication system is power on. A mobile station modem of the mobile communication system generates a second DC offset compensation signal to compensate for a detected DC offset voltage during operation of the mobile communication system subsequent to the DC offset voltage being preset. In addition, the offset compensation circuit re-presets the DC offset by generating a third DC offset compensation signal whenever the mobile communication system enters a predetermined mode of operation such as a “data send” mode.

Abstract: A wireless communications device includes an amplifier module configured to amplify a signal. The amplifier module includes a serial arrangement of amplifiers. Each of the amplifiers are designed to operate with increased efficiency for different power level ranges. The amplifiers are connectable via controllable switches. A controller, in communication with the controllable switches, selectively connects the amplifiers to increase the efficiency of the amplifier module.

Abstract: A gain controlled radio receiver for a selective call system, includes a multi-step gain controlled RF amplifier (44) coupled to receive an input signal and a measuring circuit (42) for measuring the level of a wanted frequency down converted signal. The multi-step gain controlled amplifier (44) has an input terminal (RIP, RIN), N gain stages (76A to 76E), where N is an integer of at least 2, having outputs coupled to a common output stage (82). A first of the N gain stages (76A) is coupled to the input terminal (RIP, RIN), and an (N−1) stage capacitive ladder attenuator (86) has an input coupled to the input terminal and outputs coupled respectively to an input of each of the second to Nth gain stages (76B to 76E). The measuring circuit (42) has a level control output (45) for switching-on a selected one of the gain stages which provides an amplified signal to the common output stage for frequency down conversion and demodulation.

Abstract: To solve the problems associated with conventional signal strength measurements utilizing homodyne receivers, the present invention is able to economically reduce the idle time power usage of a homodyne receiver by “powering down” a part of the homodyne receiver. With certain signal modulations, the power received in each channel of the homodyne receiver is equivalent and, as a result, the estimated received signal strength measurement calculation is simplified, reducing the power usage, which can be very useful, especially in the mobile communications industry.

Abstract: To reduce the impact of image frequencies generated by mixing an incident carrier signal down to a relatively low intermediate frequency signal used in subsequent signal processing, a mixing frequency is selected such that the generated intermediate frequency signal has a frequency offset relative to DC that is substantially that of a single channel spacing between frequency adjacent incident carrier signals, as shown in FIG. 2. Image rejection is further improved through the integration of a current-driven polyphase filter (36) directly between an input stage (Q1 to Q4) and a mixer stage (Q5 to Q12) of an image reject mixer (FIG. 4) such as to mitigate quadrature divergence between separate in-phase and quadrature paths within the image reject mixer.

Abstract: A cable modem is configured to include a tuner having a front end which includes a duplex filter stage and a decoupler stage and a rear end which includes a single conversion tuner. The duplex filter stage couples the tuner to a network, a computer system and the front end decoupler stage. Signals received from the network are directed by the front end duplex filter stage to the front end decoupler stage while signals received from the computer system are directed by the front end duplex filter stage to the network. The front end decoupler stage passes RF signals received at an input thereof to an input of the single conversion tuner coupled to an output of the front end decoupler circuit. The single conversion tuner selects, from the plurality of RF signals received thereby, an RF signal to be converted into an IF signal for output therefrom while rejecting the remainder of the plurality of RF signals.

Abstract: A technique is used in a selective call communication system (100) and in a broadcast communication system (106) to provide additional information about a broadcast to a selective call device (111). A broadcast receiver (109) receives a broadcast that includes a prompt (220), such as a FLEX.TM. logo, and an information address signal (305), such as an inaudible portion of the sound portion of the broadcast. The prompt indicates that additional information is available in a message to be transmitted by the selective call communication system. The selective call device receives the information address signal when activated to do so in response to the prompt. The selective call device receives and decodes an information address from the information address signal and uses it to recover the message at a protocol position indicated by the information address. The additional information is then recovered from the message.

Abstract: A method and apparatus for providing global message monitoring in a paging system includes a message origination and delivery device (MODD) (20). The MODD (20) includes a data structure (100) which identifies certain users as message monitoring users. Message monitoring users receive monitored page messages (300), which are duplicates of pages sent to users being monitored. The MODD (20) sends pages to a pager in the possession of the message monitoring user.

Abstract: A wireless subscriber unit (30) contains an advertisement manager (56). The advertisement manager (56) is programmed to assign an advertisement icon (54) to a message indicator (46) on the display (42) of the wireless subscriber unit (30). Assignment of the advertisement icon (54) to the message indicator (46) associated with a message (26) may be based on a predetermined algorithm in the advertisement manager (56), or based on a notification received from the wireless communication system (10).

Abstract: A portable one-way radio pager includes receiver means for receiving coded radio messages, a CPU for processing the messages, and a control memory containing at least one number referred to as "validity data" representative of a certain sum of money, the CPU being designed to decrement the validity data progressively during operation of the pager and to prevent normal operation of the pager when said validity data is less than a predetermined minimum value.

Abstract: A special function application (32) within a wireless subscriber unit (10) operates using information contained in segments of a received message (14). The information included in the received message (14) can be used in more than one special function application (32) to meet multiple end-user needs.

Abstract: A method in a communication system (100) having at least a first and a second base stations (104, 108) for communicating with selective call devices (102) includes the steps of transmitting a first signal on a first frequency that indicates an alternate frequency and transmitting second signal on the alternate frequency indicated by the first signal. The second signal has a registration threshold for controlling registration of the selective call device (102) with the second base station (108).

Abstract: A radio communication device 7 existing in a function control area 3 receives both a call signal 4 from a base station and a function control signal 5 transmitted from a function control signal transmitting device 2. The call signal 4 and the function control signal 5 have the same frequency. The call signal 4 received is converted into a predetermined block format and constitutes predetermined frames during which data errors occurred in the predetermined block is counted. After the counting, the number of data errors occurred in the predetermined block is compared with a predetermined value. On the basis of the result of comparison, it is determined whether or not the radio communication device 7 exists in a function control area 3. When it is determined that the radio communication device 7 exists in the function control area 3, the function of the radio communication device 7 is controlled and restricted.

Abstract: The message transmitter transmits a re-calling identification signal with a message, and a receiver identifies this signal. Thereby the message transmitter can indicate selectively the re-calling of the receiver. If the message is not confirmed, the receiver performs re-calling according to a previously set time interval with a second sound pattern different from the normal sound pattern for indicating that this message is an unconfirmed message until the message is confirmed. The receiver continues to perform the calling operation periodically until the receiver holder cancels the re-calling. Meanwhile the message is confirmed by switch operation with a third sound pattern of three short sounds which are not noisy.

Abstract: The invention provides an apparatus and method for processing incoming telephone calls directed to a user. A valid identification signal from the user is detected and then the user is transferred to a system command mode. In the command mode, a request from the user for information regarding a present mode by which incoming calls are processed is identified, the current mode by which incoming calls are processed is recalled from memory, and the results are transmitted to the user.

Abstract: Apparatus for communication using multiple radio processing modules is disclosed herein. The apparatus for communication mentioned above receives a first radio signal and a second radio signal from a source to acquire a first information and a second information. The first radio signal and the second radio signal is within a first frequency range and a second frequency range respectively. The first message signal and the second message signal are of a baseband range. The first information and the second information are carried by the first message signal and the second message signal respectively. The apparatus for communication mentioned above includes the following devices. A first radio processing module that transfer the first radio signal to generate the first message signal. A second radio processing module that transfers the second radio signal to generate the second message signal.

Abstract: For informing a user of a pager terminal for receiving message information attributed with a serial message number of the serial message numbers of missing message information, the pager terminal having a missing massage indicator comprises, a message status memory (17) prepared with a message reception table having a reception confirmation flag area and a reception failure flag area for each of possible serial message numbers. A logic `1` flag is set in the reception confirmation flag area corresponding to the serial message number N of the message lastly stored. When a message having a message number M is newly received, the numbers M and N are compared. When M.noteq.N+1, logic `1` flags are set in all the reception failure flag areas corresponding to the serial message numbers from N+1 to M-1 for indicating the reception failure of these messages.

Abstract: A paging system wherein each user carries a paging device adapted to receive radio frequency signals broadcast from a central paging system with a unique identification code assigned to each paging device. Each paging device includes a radio frequency transmitter and controller for controlling the radio frequency transmitter, the controller being operable in two distinct user selectable modes, the first such mode being responsive to receiving a signal broadcast by the central paging system and responding by transmitting predetermined data back to said central paging system.

Abstract: A method for automatically changing a service area of a wide area pager integrated with a Second Generation Digital Cordless Telephone (CT-2) is provided. The method includes the step of receiving service area information by the CT-2 and transmitting the service area information to the wide area pager, when a radio paging mode is performed. The service area information transmitted to the wide area pager from the CT-2 is compared with preset service area information in the wide area pager. The preset service area information in the wide area pager is then changed to the service area information transmitted to the wide area pager, when the preset service area information is not identical to the transmitted service area information.

Abstract: There is disclosed a launch delay controller, for use in a wireless messaging system having a defined coverage area. The launch delay controller controls the transmission of paging messages from a plurality of transmitters in the wireless messaging system. The launch delay controller comprises: 1) a memory capable of storing a) a delay spread associated with a selected point in the coverage area between a first signal transmitted by a first of the plurality of transmitters and a second signal transmitted by a second of the plurality of transmitters, and b) distances between the selected point and the first and second transmitters; and 2) a processor capable of determining from the delay spread and the distances an offset delay, wherein the offset delay is used by the first transmitter to delay a transmission of the first signal with respect to a transmission of the second signal, the delayed transmission of the first signal thereby reducing the delay spread.

Abstract: Call forwarding service provided to a wireless mobile communication station is controlled by barring call forwarding from the wireless mobile communication station selectively based on the location of the wireless mobile communication station.

Abstract: In a radio-paging receiver comprising a receiving arrangement (11, 12, 13) for successively receiving messages included in selective call signals as received messages, a received message storing area (202) for storing the received messages as stored messages, a character number information storing area (204) for storing the number of characters for each of the stored messages as a stored character number, an LCD (19) visually displays the stored character number for each of the stored messages with analog representation. The analog representation may be graphical representation, which is, for example, performed by using a bar graph.

Abstract: An antenna structure which has a triangular platform defining three sides, each of which sides defines respective first and second sectors, each of which sectors defines a vertex located within the triangular platform. At least one antenna is positioned on each respective side for transmitting and receiving signals substantially only in the first sector of the respective side. At least one other antenna is positioned on each respective side for transmitting and receiving signals substantially only in the second sector of the respective side.

Abstract: A communication device (125) receives a signal in which messages are included. The communication device (125) includes a decoder (215) for recovering a received message from the signal and a message status element (250) for determining whether the received message is of a first type or a second type of message. Transmission of an acknowledgment by the communication device (125) indicative of a presentation of the received message to a user occurs in response to presentation of a message of the first type, and transmission of an acknowledgment by the communication device indicative of a presentation of the received message to a user does not occur in response to presentation of a message of the second type. The communication device (125) further includes a display (230) for visually presenting information to the user by which the user is alerted to whether the received message is of the first or the second type.

Abstract: A first messaging system (112, 116) schedules (502) a first store-and-forward message (406, 408) for transmission to a subscriber unit (122) on a first channel (410) and enters (504) a second store-and-forward message (404) into a second messaging system (113, 116), the second message intended for the subscriber unit and including a scheduling instruction for receiving the first message. The second messaging system communicates the second message to the subscriber unit on a second channel (412), and the subscriber unit tunes (620) to the first channel, in accordance with the scheduling instruction, after receiving the second message. The first messaging system then transmits (506) the first message on the first channel as scheduled, and the subscriber unit receives the first message on the first channel.

Abstract: In a selective calling communication system, the number of times a paging signal is transmitted and a paging signal transmission interval can be changed in response to a request of a calling party, and the paging signal is transmitted the changed number of times and/or at changed intervals, so that the paging signal can be received at a higher probability than before, thus making it possible to realize a selective calling communication system which can improve the reliability of reception as compared with conventional systems.

Abstract: In order to estimate the number of message transmissions dispatched to a radio pager wherein messages transmitted are sequentially numbered, a transmitted signal is acquired which has been found to be directed to the pager. Thereafter, a check is made to determine if a message number included in the transmitted signal is detected. If the message number is detected, the message number detected is stored in a memory. The number of acquired transmitted signals is incremented except where the message number detected is discontinuous with a previous message number which was detected immediately before the detection of the instant message. Then the number of message transmissions is estimated or determined using the number of acquired transmitted signals, the message number detected stored in the above, and the above mentioned previous message number.

Abstract: A double conversion tuner includes a first filter that is relatively flat over a 6 MHz band at 920 MHz. A pair of series-parallel resonant circuits form notch filters that operate on the downconverted signals to economically produce a 6 MHz frequency response at 44 MHz that has excellent adjacent channel and other signal rejection.

Abstract: In a radio communication system and radio communication apparatus, the ringing sound or melody of calling notification can be altered by users. A music data receiving section, a music data storage section and a music data reproducing section are provided within a controller. A calling party transmits a calling signal in which music data is appended to the message; a called party receives the calling signal through an antenna and radio section, where a music data receiving section is used to determine whether or not music data is contained in the received message in the calling signal, and, if it is contained, to perform ringing for calling notification with a speaker by using the music data.

Abstract: If a user attempts to provide a protection attribute to a new message while the number of old messages which have a protection attribute and are retained is equal to the maximum number of protected messages, a portable radio terminal, such as a pager system, displays on an LCD 13 the oldest received message having a protection attribute. Only the messages having a protection attribute are displayed on the LCD 13 in chronological order of receipt by rotating a rotary switch 4. A message whose protection attribute is canceled is determined by pressing the rotary switch 4 while a message which the user desires to cancel is displayed. Simultaneously, the foregoing operation enables a new message which the user desires to protect to be provided with a protection attribute.

Abstract: A wireless receiver includes a variable attenuator, a signal-to-noise ratio (SNR estimator), and a received signal strength indicator (RSSI) level detector. The RSSI level of the received signal is used as a primary criterion on setting the attenuator status. Once the attenuator is set based upon the RSSI readings, an SNR check is made to determine the possible presence of IM. Then, further adjustment on the attenuator status is made according to the SNR check.

Abstract: A computer-based hand-held translator device for use in relation to preparing a numeric message for sending from a telephone having a telephone keypad to a numeric pager and also in relation to displaying an alpha message originally received as a numeric message on a numeric pager. Keystroke entry of alpha and numeric keys create alpha mode and numeric mode messages on a display. Entry of a translator actuator on the keyboard accesses a chip that translates an alpha mode message on the display to a numeric mode message on the display and that translates a numeric mode message on the display to an alpha mode message in accordance with an algorithm loaded into the chip. At the sender side the alpha message on the display is translated into a numeric mode that is entered onto a telephone keypad targeted to a pager. At the receiver side, the numeric message is entered onto the translator device and then translated to an alpha message. A personal notebook system is optionally included in the translator device.

Abstract: In a radio selective calling receiver, a control section 103 has a DTMF signal generating section 103F that converts a transmit message into a dial tone signal to output the dial tone signal. A CPU section 103B of the control section 103 can transmit a message from the DTMF signal generating section 103F in the state that a message received from another receiver is read from a RAM section 103C and displayed on a display section 10, and at this time stores the receive message and the transmit message in association with each other in the RAM section 103C. When reading the receive message, the transmit message corresponding to the receive message is also displayed on the display section 107.

Abstract: A miniature radio apparatus for use in transmission or reception of electic waves has a pair of antenna terminals insulated from each other. The pair of antenna terminals are so formed as to be brought into contact with, or to be capacitively-coupled to, different parts of the human body, respectively. One of the pair of antenna terminals is formed so as to be brought into contact with one of the arms, ears, or fingers of the user. The miniature radio apparatus also has a detection/control device for detecting whether the antenna terminals are in contact with, or capacitively-coupled to, different parts of the human body, respectively, and controlling the transmission or reception of electric waves. Consequently, it is possible to obtain a practical gain, and also to enlarge the range of communication so that the quality of communication is improved. It is, furthermore, possible to receive electric waves without an arm band antenna.

Abstract: A method, and associated apparatus, for the selective transmission of packet data to a mobile terminal operable in a radio communication system. When packet data is to be terminated at the mobile terminal, an SMS (short message service) message is first transmitted to the mobile terminal. A determination is made at the mobile terminal whether to permit transmission of packet data thereto. The packet data is transmitted to the mobile terminal if permission is granted by the mobile terminal.