Abstract: A single chip radio transceiver includes circuitry that enables received RF signals to be down-converted to baseband frequencies and baseband signals to be up-converted to RF signals prior to transmission without requiring conversion to an intermediate frequency. The circuitry includes a low noise amplifier, automatic frequency control circuitry for aligning the LO frequency with the frequency of the received RF signals, received signal strength indicators for adjusting frontal and rear amplification stages accordingly, and, finally, filtering circuitry to filter high and low frequency interfering signals, including DC offset.

Abstract: Techniques for efficient signaling to and from a plurality of mobile stations are disclosed. In one embodiment, a subset of mobile stations may be allocated a portion of the shared resource with one or more individual access grants, another subset may be allocated a portion of the shared resource with a single common grant, and yet another subset may be allowed to use a portion of the shared resource without any grant. In another embodiment, an acknowledge and continue command is used to extend all or a subset of the previous grants without the need for additional requests and grants, and their associated overhead. In one embodiment, a traffic to pilot ratio (T/P) is used to allocate a portion of the shared resource, allowing a mobile station flexibility in selecting its transmission format based on T/P.

Abstract: A full-duplex transceiver using a method immunizing itself against self-jamming. The transceiver includes a receiver and a transmitter. The receiver includes a frequency immunization converter and a high pass IF filter. The transmitter transmits a TX signal. The receiver receives an RX signal and simultaneously receives a portion of the power of the TX signal as an undesired TX jamming signal. The frequency immunization converter uses the center frequency of the TX signal for downconverting the RX signal to an IF signal and simultaneously downconverting the TX jamming signal to near zero frequency. The high pass IF filter passes the IF signal and blocks the signal at near zero frequency. As a consequence of the downconversion using the TX frequency, a second LO frequency is controlled for avoiding image frequencies.

Abstract: The invention provides a communication semiconductor integrated circuit device (RF IC) capable of pulling in the frequency of a PLL circuit to a desired set frequency at high speed even in the case where a frequency settable range of the PLL circuit is wide without providing a current source other than a current source for charging and discharging in an normal operation. An oscillator as a component of a PLL circuit is constructed so as to be operative in a plurality of bands. In a state where a control voltage of the oscillator is fixed to a predetermined value, an oscillation frequency of the oscillator is measured in each of bands and stored in a storing circuit. A set value for designating a band supplied at the time of PLL operation is compared with the stored measured frequency value. From a result of comparison, a band to be actually used in the oscillator is determined, and a frequency difference between the maximum frequency of the selected band and the set frequency is obtained.

Abstract: An exemplary embodiment of the present invention described and shown in the specification and drawings is a transceiver with a receiver, a transmitter, a local oscillator (LO) generator, a controller, and a self-testing unit. All of these components can be packaged for integration into a single IC including components such as filters and inductors. The controller for adaptive programming and calibration of the receiver, transmitter and LO generator. The self-testing unit generates is used to determine the gain, frequency characteristics, selectivity, noise floor, and distortion behavior of the receiver, transmitter and LO generator. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or the meaning of the claims.

Abstract: A wireless communication RF circuit includes a transmitting-and-receiving antenna, a modulator circuit, an SPST switching circuit, and a demodulator circuit, which are arranged in a sequence. Upon signal reception, the SPST switching circuit is switched ON, and the demodulator circuit extracts a signal wave from a signal received by the antenna and outputs the signal wave to a control circuit. Upon signal transmission, the SPST switching circuit is switched OFF, and the modulator circuit mixes transmission data supplied from the control circuit with a carrier and outputs the carrier to the antenna. Only a single antenna is required. Upon signal reception, the influence of the modulator circuit is negligible. Upon signal transmission, the SPST switching circuit is switched OFF, thus the effect of the demodulator circuit is negligible, which greatly reduces loss.

Abstract: An exemplary embodiment of the present invention described and shown in the specification and drawings is a transceiver with a receiver, a transmitter, a local oscillator (LO) generator, a controller, and a self-testing unit. All of these components can be packaged for integration into a single IC including components such as filters and inductors. The controller for adaptive programming and calibration of the receiver, transmitter and LO generator. The self-testing unit generates is used to determine the gain, frequency characteristics, selectivity, noise floor, and distortion behavior of the receiver, transmitter and LO generator. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or the meaning of the claims.

Abstract: Radio transceiver, in particular, a mobile telephone having a transmitter output stage, a receiver part, a transmission/reception antenna which is assigned jointly to the transmitter output stage and the receiver part, a transmission band-transmitting filter and a reception band-transmitting filter, having a compensation element, connected between the output of the transmitter output stage and the input of the receiver part, for compensating crosstalk of a transmission signal element onto the receiver part.

Abstract: A chip-on-chip-structure semiconductor device for a radio communication device, having a base band chip and a high-frequency chip piled up on and bonded to the surface thereof. The base band chip has a low-frequency signal processing unit for processing a signal in a first frequency band. The high-frequency chip has a high-frequency signal processing unit for processing a signal in a second frequency band of which frequency is higher than that of the first frequency band.

Abstract: A transceiver having a transmit/receive switch. The transmit/receive switch includes: a common port adapted for coupling to an antenna element; a transmit port; a receive port and a matched port. The transceiver includes a second switch. The second switch has: a common port adapted for coupling to an input/output port through a gain/phase control unit; a transmit port; a receive port and a matched port. The transceiver includes a balanced amplifier. The balanced amplifier includes a pair of input ports. A first one of the pair of input ports is coupled to receive port of the transmit/receive switch, and a second one of the pair of input ports is coupled to the transmit port of the second switch. The balanced amplifier includes a pair of output ports. A first one of the pair of output ports is coupled to the transmit port of the transmit/receive switch and a second one of the pair of ports is coupled to the receive port of the second switch.

Abstract: A radio transceiver comprises a reception path, a transmission path, and a frequency generator with a programmable phase lock loop. The reception path, the transmission path, and the frequency generator share a maximum amount of common circuitry to facilitate implementation of the entire radio transceiver on a single integrated circuit. The reception path includes an amplifier and a quadrature mixer for producing low intermediate frequency signals. The transmission path can be controlled by either a modulated voltage controlled transmitter or an in-phase and quadrature modulator transmitter.

Abstract: An AM receiver incorporates an antenna, a transistor, a current source, and a power supply. The antenna is connected to a gate electrode of the transistor and through a link to a signal earth. In operation, the antenna receives radiation and generates a corresponding input signal which propagates to the gate electrode. The transistor is operable to process the input signal in two steps, namely to reflectively amplify the input signal to generate a correspondingly reflectively amplified input signal at the gate electrode in a first step, and amplitude demodulate the amplified input signal in a second step. The transistor is operable in a non-linear region of its current/voltage characteristic whereas it simultaneously provides reflective amplification and signal demodulation, namely the two steps occur simultaneously.

Abstract: A wireless computer data network includes several untethered mobile units that make ad-hoc data connections with an Internet-connected base station using the IEEE-802.11a standard. Each unit includes a radio transceiver fully integrated on a single semiconductor chip. The receiver portion is a double-conversion superheterodyne type, and shares the same intermediate and local oscillator frequencies with a two-stage up-conversion transmitter. Two on-chip synthesizers that each include a voltage-controlled oscillator and phase-locked loop can be operated independently for each conversion stage, or operated in offset mode. External reference frequencies can be injected for voltage-controlled oscillator and phase-locked loop testing, chip characterization, and automatic compensation modeling. Each mobile and base unit can be outfitted with transmit/receive antenna transfer switches, RF-power amplifiers, and low-noise receiver amplifiers to increase operating range.

Abstract: A signal interfacing technique for connecting signals between a signal processing device and a radio integrated circuit (IC) involving multiplexing two or more signals on a connection pin between the radio IC and a signal processing device. According to one technique, transmit and receive signals are multiplexed such that during a transmit mode a transmit signal is coupled on the connection pin from the signal processing device to the radio IC, and during a receive mode a receive signal is coupled from the radio IC on the connection pin to the signal processing device. According to another technique, in-phase (I) and quadrature (Q) signals are multiplexed on a connection pin during both transmit and receive modes.

Abstract: A lightweight millimeter wave outdoor unit includes a lightweight housing with a heat sink and mounting member configured for mounting on the antenna to form a wireless link. A millimeter wave transceiver board is formed of ceramic material and mounted within the housing. It includes a millimeter wave transceiver circuit that has microwave monolithic integrated circuit (MMIC) chips and operable with the transmit and receive boards. An intermediate frequency (IF) board has components forming an intermediate frequency circuit operable with the millimeter wave transceiver circuit. A frequency synthesizer board has a signal generating circuit for generating local oscillator signals to the transceiver circuit. A controller board has surface mounted DC and low frequency discrete devices thereon forming power and control circuits that supply respective power and control signals to other circuits on other boards.

Abstract: Only a first radio station is equipped with a local oscillation signal source. A signal transmitted to a second radio station includes local oscilaation signal components used to up-convert a modulated intermediate frequency band signal in addition to intermediate frequency band signal components. The second radio station that receives the signal from the first radio station extracts and regenerate the local oscillation signal used at the first radio station using a local oscillation signal regenerator. The extracted and regenerated local oscillation signal is used to down-convert modulated radio signal components to the intermediate frequency band and simultaneously up-convert to the radio frequency band the modulated intermediate frequency band signal to be transmitted to the first radio station.

Abstract: An exemplary embodiment of the present invention described and shown in the specification and drawings is a transceiver with a receiver, a transmitter, a local oscillator (LO) generator, a controller, and a self-testing unit. All of these components can be packaged for integration into a single IC including components such as filters and inductors. The controller for adaptive programming and calibration of the receiver, transmitter and LO generator. The self-testing unit generates is used to determine the gain, frequency characteristics, selectivity, noise floor, and distortion behavior of the receiver, transmitter and LO generator. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or the meaning of the claims.

Abstract: A two part cellular radio telephone in which a separable part is charged from a cellular transceiver portion.

Abstract: Techniques to correct for phase and amplitude mismatches in a radio device in order to maintain channel symmetry when communicating with another device using MIMO radio communication techniques. Correction for the amplitude and phase mismatches among the plurality of transmitters and plurality of receivers of a device may be made at baseband using digital logic (such as in the modem) in the receiver path, the transmitter path or both paths of that device. In a device, amplitude and phase offsets are determined among the plurality of radio transmitter and radio receiver paths by measuring phase and amplitude responses when supplying a signal to a transmitter in a first antenna path of the device and coupling the radio signal from a first antenna to a second antenna path of that device where the signal is downconverted by a receiver associated with the second antenna path, and similarly coupling a signal from the second antenna path to the first antenna path.

Abstract: The invention is directed to an apparatus, method and system for providing reduced power consumption, fast processing of digitized communication signals and relatively easy reconfiguration for different applications, such as communication protocols/standards. The invention recognizes that the processing of signals associated with different types of communication standards can be recharacterized as deterministic data flows. Also, for each deterministic data flow, several of the same categories of computation are performed in substantially the same manner, albeit in a different order or somewhat differently, that is unique to a particular application. Based on this recharacterization, the invention divides the processing of the deterministic data flow for a communication signal among several Class processors that are separately configurable to optimize their particular category/class of computation in the processing of the signal.

Abstract: A packet-based wireless transceiver that transmits and receives data packets includes a transceiver component having an adjustable performance parameter. A calibration circuit adjusts the performance parameter of the transceiver component at times synchronized with the data packets. A calibration signal generator generates calibration signals based on the performance parameter and outputs the calibration signals to the transceiver component. A comparator receives the outputs of the transceiver component and generates a difference signal. A calibration adjustment circuit communicates with the calibration signal generator and the comparator and adjusts the performance parameter to reduce the difference signal. Alternately, a reference signal generator generates a reference signal. A comparator receives the reference signal and a second signal from the transceiver component and generates a difference signal.

Abstract: A radio frequency (RF) integrated circuit (IC) includes a local oscillation module, analog radio receiver, analog radio transmitter, digital receiver module, digital transmitter module, and digital optimization module. The local oscillation module is operably coupled to produce at least one local oscillation. The analog radio receiver is operably coupled to directly convert inbound RF signals into inbound low intermediate frequency signals based on the local oscillation. The digital receiver module is operably coupled to process the inbound low IF signals in accordance with one of a plurality of radio transceiving standards to produce inbound data. The digital transmitter is operably coupled to produce an outbound low intermediate frequency signal by processing outbound data in accordance with the one of the plurality of radio transceiving standards. The analog radio transmitter is operably coupled to directly convert the outbound low IF signals into outbound RF signals based on the local oscillation.

Abstract: The present invention provides a transceiver apparatus that permits miniaturization even when the antenna thereof is an unbalanced circuit and the transmitter circuit section and receiver circuit section thereof are balanced circuits. The transceiver apparatus is constituted comprising: a semiconductor integrated circuit device that mounts on the same semiconductor chip a balanced receiver circuit 41 for receiving a received signal as a differential input and balanced transmitter circuit 52 for outputting a transmitted signal as a differential output, and that has at least two terminals 71,72 connected to connecting nodes that connect the balanced receiver circuit 41 and the balanced transmitter circuit 52; first and second capacitors C2,C3 connected to the terminals 71, 72 respectively; an external inductor L1 connected to the first and second capacitors C2, C3; a band pass filter 2 and an antenna 1 coupled to the first capacitor C2; and a third capacitor C1 connected to the second capacitor C3.

Abstract: An exemplary embodiment of the present invention described and shown in the specification and drawings is a transceiver with a receiver, a transmitter, a local oscillator (LO) generator, a controller, and a self-testing unit. All of these components can be packaged for integration into a single IC including components such as filters and inductors. The controller for adaptive programming and calibration of the receiver, transmitter and LO generator. The self-testing unit generates is used to determine the gain, frequency characteristics, selectivity, noise floor, and distortion behavior of the receiver, transmitter and LO generator. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or the meaning of the claims.

Abstract: A remotely mountable weatherproof bi-directional, half-duplex switching amplifier system is designed to provide maximum range for low power half-duplex radios such as Spread Spectrum radio transceivers. This invention automatically senses when to go into the transmitter amplification mode and puts all the transmit power right at the antenna. In the receive mode, it provides low noise pre amplification of received signals at the antenna thereby minimizing or even eliminating the effects of the coaxial transmission line from the radio transceiver to the remote location of the antenna. The invention is preferred to be in a waterproof enclosure adjacent to the antenna mounted to a pole and powered by a DC injector and excited by a transceiver, both pole and injector located remote from the mounting pole and also includes an improved electrostatic overvoltage protection device.

Abstract: The present invention provides a communication terminal that enables precise communications with optimum receive sensitivity at any time regardless of any change in peripheral environments of an antenna thereof. The communication terminal including means for transmitting and receiving radio waves is provided with a training mechanism for enabling the communication terminal itself to conduct training mode for tuning receive sensitivity, and switching mechanism for switching between normal communication mode and the training mode. The communication terminal is particularly useful as a communication terminal for automobile in the Intelligent Transport System or the like.

Abstract: The invention relates to the field of methods and arrangements pertaining to transceivers. The object of the invention is to enable transceivers to be used more simply and more cheaply. This is achieved with an improved method of calibrating transceivers, and with transceivers that can be calibrated in accordance with the method. A sequence of signal connections (60–70) is established between a transmitter chain (3) and a receiver chain (5) in a transceiver. A corresponding sequence of signal paths is established from a baseband stage in the transmitter chain to a baseband stage in the receiver chain. Each signal path includes at least one specific component that shall be calibrated with the use of the established signal path, wherein any further components in said signal path will have already been calibrated with the use of earlier established signal paths.

Abstract: The invention relates to a method for implementing a transceiver, in which method radio-frequency signals are transmitted and received with a transceiver for communicating information. A radio-frequency signal received at a receiving stage is subjected to at least a first filtering step, in which a desired receiving signal is separated from the signal with a filter. A signal to be transmitted at a transmission stage is subjected to at least a second filtering step, in which a desired transmission signal is separated from the signal with a filter, to be transmitted. In the method, the same filter is used at least partly in said first and second filtering steps.

Abstract: An exemplary embodiment of the present invention described and shown in the specification and drawings is a transceiver with a receiver, a transmitter, a local oscillator (LO) generator, a controller, and a self-testing unit. All of these components can be packaged for integration into a single IC including components such as filters and inductors. The controller for adaptive programming and calibration of the receiver, transmitter and LO generator. The self-testing unit generates is used to determine the gain, frequency characteristics, selectivity, noise floor, and distortion behavior of the receiver, transmitter and LO generator. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or the meaning of the claims.

Abstract: In a PLL circuit, and a wireless mobile station with that PLL circuit, an LPF charging constant current source, a discharging constant current source and a high-speed charging constant current source are connected to an output terminal of a phase comparator with current mode output. When a convergence frequency of the PLL circuit is low, an input voltage of a VCO is increased from OV so as to be converged by using the constant current source. However, when the convergence frequency of the PLL circuit is high, the input voltage of the PLL circuit is temporarily increased to the maximum voltage by using the constant current source. Thereafter, the input voltage is gradually dropped from the maximum voltage so as to be converged by using the constant current source.

Abstract: A receiving section has one crystal resonator 122, an inductor 124 able to be connected in series to the crystal resonator 122, and a channel change-over switch 123 for switching whether the inductor 124 is connected to the crystal resonator 122 and the ground, or the crystal resonator 122 is directly connected to the ground, and an adjusting change-over switch 125. A transmitting section has one crystal resonator 321, plural frequency setting adjusting circuits 312,313 each including an inductor 314,316 for determining a frequency oscillated from an oscillator, and a switching connection switch 318 for switching and connecting one of the plural frequency setting adjusting circuits 312,313 to a modulating circuit 320 connected to the crystal resonator 321.

Abstract: The invention provides a signal processing semiconductor integrated circuit of the direct conversion system, which includes a dummy amplifier having the same circuit configuration as a low noise amplifier being the first stage amplifier, in which the DC offset calibrations on the subsequent stage amplifiers are carried out during shifting into the reception mode in a state that the low noise amplifier is deactivated and the dummy amplifier is activated. Thereby, the invention achieves to suppress generation of the DC offsets resulting from the leakage noises of the local oscillator during shifting into the reception mode, and to enhance the reception sensitivity.

Abstract: In a multi-band radio terminal apparatus, when communication frequency bands are switched, a reception intermediate frequency is selected to be equal to each other in respective communication frequency bands. As a result, the circuit arrangements of this multi-band radio terminal apparatus succeeding to the intermediate frequency signal circuit stage are commonly used in the respective communication frequency bands. While a local oscillator signal is produced by a voltage-controlled oscillator, a phase-locked loop, and a doubler, in a case where communication is established within a plurality of communication frequency bands, the transmission/reception frequency intervals are different from each other. A mixer for a reception system and a mixer for a transmission system are commonly used so as to convert the frequency of the local oscillator signal into a frequency existing between the communication frequency and the intermediate frequency.

Abstract: In a multi-band radio terminal apparatus, even when communication frequency bands are switched, a reception intermediate frequency is selected to be equal to each other in the respective different communication frequency bands. The circuit arrangements of this multi-band radio terminal apparatus succeeding to the intermediate frequency signal circuit state are commonly used in the respective communication frequency bands. A local oscillator signal is produced by a voltage-controlled oscillator, a phase-locked loop, and a doubler, such that a communication is established within a plurality of communication frequency bands, the transmission/reception frequency intervals of which are different from each other. A mixer for reception system and a mixer for a transmission system are commonly used to convert the frequency of the local oscillator signal into a frequency existing between the communication frequency and the intermediate frequency.

Abstract: A multiband high-frequency switch that is mainly used for mobile phones, comprising a strip line formed of the series connection of first and second strip lines. A second transmitting port is connected to the connection point of the strip lines connected in series via a third diode, and a second control port is connected between the second transmitting port and the third diode. In addition, first and second receiving ports are connected to the receiving-side port of the high-frequency switch via a diplexer.

Abstract: A system and method for optimizing transmission of radio frequency communication link signals in a radio frequency communications network comprises determining a statistical difference between a mean radio frequency communication link propagation loss value based on a set of measured radio frequency communication link propagation loss values, and a radio frequency communication link propagation loss model value; calculating a signal to noise ratio of a radio frequency communication link signal; computing a confidence interval based on a measured signal to noise threshold ratio of a measured radio frequency communication link signal, and a standard deviation associated with the calculated signal to noise ratio; assigning a probability value based on the confidence interval; and generating a radio frequency communication link packet completion rate performance level based on the probability value. The transmission of radio frequency communication link signals occurs in either jamming or no jamming situations.

Abstract: A transmit/receive switch for a system operating over a range of frequencies is provided. The switch comprises a pair of quadrature hybrid circuits and a switching means for coupling the pair of circuits. When the switch is operating in a transmit mode, the hybrid circuits provide a low loss path between a transmitter. When the switch is operating in a receive mode, the hybrid circuits provide a high isolation from the RF coil to a pre-amplifier.

Abstract: A GPS receiver module (1) for receiving GPS signals and for determining position data therefrom is described, which is characterized in particular by a communications sub-module (3), to which the position data determined can be fed and by means of which said data can be converted into a format suitable for transmission to an a external appliance. The communications sub-module (3) is preferably a Bluetooth (BT) sub-module, by means of which the position data can be converted according to the Bluetooth standard and transmitted by wireless means. A dual band antenna particularly suitable for use with the GPS receiver module is furthermore described, by means of which it is not only possible to receive GPS signals, but also to establish a communications link with external appliances.

Abstract: A transceiver suitable for larger scale of integration employs direct conversion reception for reducing the number of filters. Also, the number of VCOs is reduced by utilizing dividers to supply a receiver and a transmitter with locally oscillated signals at an RF band. Dividers each having a fixed division ratio are used for generating locally oscillated signals for the receiver, while a divider having a switchable division ratio are used for generating the locally oscillated signal for the transmitter. In addition, a variable gain amplifier for baseband signal is provided with a DC offset voltage detector and a DC offset canceling circuit for supporting high speed data communications to accomplish fast cancellation of a DC offset by eliminating intervention of a filter within a feedback loop for offset cancellation.

Abstract: A radio circuit that includes a radio front-end for receiving a radio signal and converting the radio signal to a first intermediate frequency signal and a second intermediate frequency signal. The radio circuit also includes an analog back-end having a plurality of inputs for receiving the first intermediate frequency signal and for processing the first intermediate frequency signal in response to digital signals. Also included is a digital back-end having a plurality of inputs for receiving the second intermediate frequency signal and for processing the second intermediate frequency signal in response to the digital signals.

Abstract: Method for segmented message transmission wherein each message is first divided into segments and the segments are fragmented. A segment parameter is applied to each segment, and a segment identifier to each fragment. The fragments are provided to a lower level for preparation into frames for transmission. One embodiment is applied to the transmission of short duration messages, such as control messages. On receipt of a frame within a segment, a timer is initiated having an expiration period. Receipt of a next frame in the segment stops the timer. Expiration of the expiration period for a timer indicates that a next sequential frame is lost.

Abstract: A lightweight millimeter wave outdoor unit includes a lightweight housing with a heat sink and mounting member configured for mounting on the antenna to form a wireless link. A millimeter wave transceiver board is formed of ceramic material and mounted within the housing. It includes a millimeter wave transceiver circuit that has microwave monolithic integrated circuit (MMIC) chips and operable with the transmit and receive boards. An intermediate frequency (IF) board has components forming an intermediate frequency circuit operable with the millimeter wave transceiver circuit. A frequency synthesizer board has a signal generating circuit for generating local oscillator signals to the transceiver circuit. A controller board has surface mounted DC and low frequency discrete devices thereon forming power and control circuits that supply respective power and control signals to other circuits on other boards.

Abstract: A power mixer architecture for a transmitter chip is disclosed. The power mixer architecture is a mixing stage including one or more upper trees, and one or more lower trees. Each lower tree is selectively activated to receive current biasing signals, and current intermediate frequency signals. Upon receipt, the activated lower tree activates a corresponding upper tree to receive one or more amplified current intermediate frequency signals from the lower tree. In conjunction with a reception of voltage local oscillating signals, the upper tree provides voltage radio frequency signals. The gain of the lower tree is designed to be constant over any variance in a temperature, supply voltage or processing performance of the transmitter chip.

Abstract: A method and device are provided for the wireless transmission of voice data between at least two terminals, whereby the voice data is transmitted in data packets in predefined time frames with multiple redundancies and in time intervals at different frequencies. The present invention is characterized in that the transmission takes place at different frequencies, at least with regard to a pair of redundant data records.

Abstract: In order to compensate for performance degradation caused by inferior low-cost analog radio component tolerances of an analog radio, a future system architecture (FSA) wireless communication transceiver employs numerous digital signal processing (DSP) techniques to compensate for deficiencies of such analog components so that modern specifications may be relaxed. Automatic gain control (AGC) functions are provided in the digital domain, so as to provide enhanced phase and amplitude compensation, as well as many other radio frequency (RF) parameters.

Abstract: An embedded digitization system which enables a military platform to receive, transmit and process a variety of types of information for a variety of purposes. The system includes a mission processing capability, a digital message communications capability, a time and position location and navigation capability, a weapons delivery system aim and shoot capability, a sensor input processing capability, a user interface capability, and an input/output processing capability. The system exchanges information through digital message communications with other systems in a theater of operation. Information exchanged and processed by the system includes command and control information, situational information, intelligence information, mission information and host platform information.

Abstract: Proposed by the invention is a device for the bidirectional transfer of audio and/or video signals, in particular in the context of sound and/or image reports, with: at least one means (6) for providing an audio input signal; a first mixing device (10), which is connected to the means (6) for providing the audio input signal and which is designed to output a mixed audio transmission signal; a transmission and/or reception device coupled to the first mixing device (10) for transmitting the mixed audio transmission signal and/or receiving an audio reception signal; a control device (22) coupled to the first mixing device (10) for controlling the first mixing device (10); a compression and/or decompression device (12, 32) for compression of the mixed audio transmission signal or, as the case may be, for decompression of the audio reception signal, which compression and/or decompression device is connected to the first mixing device (10) for taking up the mixed audio transmission signal or, as the case may

Abstract: A circuit and method for reducing local oscillator frequency transmission in a homodyne, or direct conversion, radio transceiver using I/Q modulation/demodulation minimizes local oscillator leakage to the antenna and its subsequent reception by the receiver by interfacing I/Q input signals to the modulator in a controlled manner so as to increase isolation during reception by presenting high impedance states to the I/Q modulator input terminals during reception thereby nulling the carrier during reception.

Abstract: A radio device requires a tunable transceiver such that the transceiver can be accurately set to a desired frequency. When a signal with known frequency accuracy is being received, an offset detector can determine the frequency offset generated by the transceiver due to improper tuning. An automatic frequency control (AFC) system (100) is comprised of a tunable transceiver, an adaptive detector (102) for comparing an incoming sample from the tunable transceiver to an adaptive maximum deviation threshold for determining if a sample from the tunable transceiver should be used for the direct current (DC) component of the AFC, an offset detector (103) and an AFC control processor (105) for utilizing information from the offset detector to reduce the inaccuracy in frequency by tuning the transceiver towards the received signal frequency. The AFC control processor (105) utilizes one of more threshold levels for defining a maximum correction threshold (311) based upon the desired maximum offset correction.

Abstract: There is disclosed a receiver which solves such a problem as to strictly realize channel selection filter characteristics in extracting a narrow band signal from a broad band signal by digital signal processing in a conventional direct conversion circuit and which improves an image rejection ratio and which can reduce a load of hardware or processing to realize a channel selection filter for extracting the narrow band signal.