Abstract: An apparatus comprises a die comprising a plurality of switch/router circuits; and a plurality of additional dies. Each respective one of the plurality of additional dies comprises: a respective network interface, which is electrically coupled to a respective one of the plurality of switch/router circuits; and a respective interconnection test logic, which is electrically coupled to the respective network interface and the interconnection test logic in at least one other one of the plurality of additional dies.

Abstract: A method is provided for automatically providing remote services for a mobile device having an established relationship with a server of a home network. After the relationship between the mobile device and the server has been set-up and the device detects a local network that is separate and remote from the home network, a connection is automatically established between the mobile device and a local network. The device then automatically establishes an Internet connection with the server through the local network, and transmits to the server information that was stored in the mobile device when the relationship was established. In response to the server recognizing the device through the transmitted information, the server automatically activates at least one service to initiate a transfer data, such as uploading images between the device and the server through the local network.

Abstract: A device is provided for use of an antennal base formed of two antennas which pick up the emissions present and produce two radioelectric signals S1 and S2. These two signals are used to produce at least one intermediate-frequency signal Fl by demodulation of one of the two signals by the other (autotransposition). The demodulation is carried out by firstly transposing one of the signals, S1 for example, around a given frequency F1, the signal S2 being preserved around its initial central frequency F0. Thus, whatever the central frequency F0 of the emission picked up by the antennas, the demodulation produces a signal of central frequency F1, thereafter demodulated into a given intermediate frequency Fl by a local oscillator of constant frequency F2=F1+Fl. The device is applied to the production of a device for detecting emissions and for characterizing the emissions picked up.

Abstract: Some demonstrative embodiments include devices, systems and/or methods of processing single-carrier wireless communication signal. For example, a device may include a receiver to receive an analog single-carrier wireless communication signal representing a first plurality of time-domain samples at a first sampling rate; to convert the analog single-carrier wireless communication signal into a digital signal including a second plurality of time-domain samples at a second sampling rate, which is greater than the first sampling rate; to convert the second plurality of time-domain samples into a first plurality of frequency-domain samples; and to map the first plurality of frequency-domain samples into a second plurality of frequency-domain samples at the first sampling rate.

Abstract: A system includes a polyphase multirate filter and a controller which, responsive to detecting a data stream: measures a current phase relationship between a current resampling filter input clock signal and a current multirate output clock signal; identifies, based on a mapping of the measured phase relationship within a pre-generated quantized mapping table, an initial polyphase filter coefficient index corresponding to the measured phase relationship; selects, based on the initial polyphase filter coefficient index identified, a corresponding polyphase filter component from within the multirate filter; configures the multirate filter to pass data from the data stream through the corresponding polyphase filter component to generate an initial output data sample; updates the initial polyphase filter coefficient index to a calculated next polyphase filter coefficient index value, in response to a request for generation of a next output data sample; and self-corrects the multirate filter responsive to a pre-ide

Abstract: A single sideband mixer is constructed with digital logic elements such as T-type flip-flops and inverters and with FETs, and the resulting mixer circuit simultaneously improves control over the frequency resolution, noise floor and operating frequency range. The use of this group of elements also allows the mixer circuit to be easily realized in an integrated circuit.

Abstract: A single side band mixer is composed of standard digital logic elements and field effect transistors, forming a pair of quadrature generators coupled with a mixer-splitter circuit. This design results in a single side band mixer with a bandwidth from DC to at least 100 MHz when realized with CMOS digital logic circuitry. This design allows the single side band mixer to bring particular improvement to circuits including frequency synthesizers, quadrature demodulators and up-converters.

Abstract: An apparatus for recovering carrier wave in digital broadcasting receiver and a method therefore are disclosed which are capable of easily detecting and correcting frequency offsets of carrier wave without recourse to a pilot signal in a digital broadcasting receiver receiving a broadcasting signal of vestigial sideband (VSB) modulation system, thereby recovering the carrier wave, wherein, to this end, a complex sine wave whose central frequency is 1/n the symbol frequency is multiplied to generate a real component and imaginary Offset Quadrature Amplitude Modulation (OQAM) signals to calculate a phase error value from the real and imaginary component OQAM signals, to generate a complex sine wave compensating the calculated phase error value, to multiply the complex sine wave by the complex signal outputted from the phase splitter and to convert the complex signal to a baseband signal whose frequency offset is corrected.

Abstract: A frequency synthesizer is built using a phase locked loop incorporating a single side band mixer in the input. The single side band mixer is preferably realized with digital logic and FETs, and the resulting frequency synthesizer simultaneously improves control over the frequency resolution, noise floor and operating frequency range.

Abstract: Frequency translation, such as frequency up conversion of a video baseband or intermediate frequency to a desired frequency division broadcast channel, is provided utilizing a single sideband or image reject mixer and filtering having relaxed selectivity requirements. According to a preferred embodiment, a first single sideband mixer accepts an input signal at an intermediate frequency and up converts this signal to a high intermediate frequency. The image rejection provided by the single sideband mixer in combination with simple filtering provide sufficient signal quality to achieve desired levels of desired signal isolation, such as on the order of 40 dB. Preferably, a second single sideband mixer accepts the high intermediate frequency signal and down converts this signal to a desired transmission or broadcast frequency.

Abstract: Single sideband (SSB) mixers and methods of extracting a SSB signal, which are capable of outputting a single frequency using a plurality of mixers and a local oscillating frequency without having to implement phase-shifting. In one embodiment, a single sideband (SSB) mixer comprises a first mixer and a second mixer, wherein the first and second mixers multiply an input IF (intermediate frequency) signal by a local IF signal having the same frequency of the input IF signal; a band-pass filter which passes upper sideband signal output from the first mixer; a third mixer which multiplies the upper sideband signals output from the band-pass filter by a LO (local oscillating) signal; a fourth mixer which multiplies the signals output from the second mixer by the LO signal; and a subtraction device that subtracts output signals of the third mixer from output signals of the fourth mixer.

Abstract: A method and circuit for receiving a radio frequency signal by receiving and amplifying the radio frequency signal to produce a received signal and generating first and second clock signals corresponding to first and second channel signals, respectively, of the received signal and multiplying the received signal with the clock signals to obtain the channel signals. Pre-selectivity filtering of the received signal is performed by filtering the first channel using a first impedance, filtering the second channel using a second impedance, and converting the first and second impedances with respect to one another through a first gyrator. Amplitude limiting of the first and second channels is performed to obtain first and second amplitude limited channels. Poly-phase selectivity filtering of the first and second amplitude limited channels is performed to obtain first and second selectivity filtered channels. The selectivity filtered channels are demodulated to obtain a data signal.

Abstract: A frequency synthesizer is built using a phase locked loop incorporating a single side band mixer either in the feedback loop or in the input. The single side band mixer is preferably realized with digital logic and FETs, and the resulting frequency synthesizer simultaneously improves control over the frequency resolution, noise floor and operating frequency range.

Abstract: Aspects of the method and system for rejecting single sided leakage into an amplitude modulated channel may comprise an AM demodulator for demodulating a received composite broadcast signal's control channel to generate an amplitude modulated (AM) component. A PM demodulator may demodulate a received composite broadcast signal's control channel to generate a phase modulated (PM) component. At least one subtractor may subtract an AM leakage component and a PM leakage component contributed by the single sided leakage in the received composite broadcast signal's control channel. The system may comprise at least one of each of AM and PM bandpass filters and envelope detectors that filter and detect envelopes of the AM and PM components at 982.5 Hz and 922.5 Hz.

Abstract: In a dual-channel HD radio receiver, when the broadband filter channel is compromised, the broadband channel is inactivated and the narrowband channel is activated. By mixing the signals of the two channels during the change, undesirable audio artifacts can be minimized.

Abstract: At the transmitter of a transmitter and receiver apparatus for Multiple Input/Multiple Output MultiCarrier-Code Division Multiple Access (MIMO MC-CDMA) systems, modified orthogonal transmit diversity (MOTD) encoders are used for increasing space and time transmission diversity. A P-way combiner is used to connect the MOTD encoders and P multi-carrier modulators. Each modulator is connected to a set of antennas. At the receiver, each multi-carrier demodulator has an amplitude/phase compensator to compensate distortion at every sub-carrier. Similarly, a combiner is used to connect the demodulators and the MOTD decoders. As a result, space, time, and frequency diversity can be explored.

Abstract: Carrier frequency detection for an N-ary modulated signal is achieved by digitizing the N-ary modulated signal, frequency shifting the digitized N-ary modulated signal to prevent aliasing, raising the frequency-shifted signal to the Nth power, transforming the raised signal to frequency domain data and determining an initial maximum frequency peak, iteratively fine shifting the frequency of the N-ary modulated signal around the initial maximum frequency peak and repeating the raising, transforming and determining steps to obtain a plurality of maximum frequency peaks, and calculating the carrier frequency from the maximum frequency peaks and the total related frequency shift.

Abstract: A signal reception device is disclosed that is able to improve interference cancellation capabilities even when signals having different center frequencies exist on the same frequency band. The signal reception device includes an interference suppression unit to generate replicas of plural signals in the received signal and separate the signals by suppressing interference signals. The interference suppression unit includes a signal phase rotator to rotate phases of the signal candidates at preset respective rotational frequencies, the preset rotational frequencies being related to respective center frequencies of the signals in the received signal; a rotational frequency controller to set the preset rotational frequencies; and a replica generator to generate the replicas of the signals by using the phase-rotated signal candidates.

Abstract: Frequency translation, such as frequency up conversion of a video baseband or intermediate frequency to a desired frequency division broadcast channel, is provided utilizing a single sideband or image reject mixer and filtering having relaxed selectivity requirements. According to a preferred embodiment, a first single sideband mixer accepts an input signal at an intermediate frequency and up converts this signal to a high intermediate frequency. The image rejection provided by the single sideband mixer in combination with simple filtering provide sufficient signal quality to achieve desired levels of desired signal isolation, such as on the order of 40 dB. Preferably, a second single sideband mixer accepts the high intermediate frequency signal and down converts this signal to a desired transmission or broadcast frequency.

Abstract: A transmitter shifts a baseband data signal having a bandwidth of 2?M using a tone signal having a frequency ?M, which centers a sideband of the data signal at zero frequency. The transmitter then filters the shifted signal to filter out the non-centered sideband, and then adds the tone signal to form a composite signal. The transmitter upconverts the composite signal during a first operational mode using a RF signal having a frequency ?C equal to a center frequency of a channel. In a second operational mode, the transmitter upconverts a DC level using the same RF signal. The upconverted DC level can be used as a continuous wave carrier signal having a frequency ?C. The transmitter has a single RF oscillator to output both a SSB signal centered at frequency ?C during the first mode and a carrier signal of frequency ?C during the second mode.

Abstract: An analog signal scrambler/de-scrambler includes a receiver for receiving an analog signal and converting the signal into an intermediate frequency signal. A generator generates a pseudo-random gaussian frequency distribution signal, which is multiplied with the intermediate frequency signal by a frequency converter to scramble/de-scramble the analog signal.

Abstract: The invention relates to an apparatus of transmitter and receiver for Multiple Input/Multiple Output MultiCarrier-Code Division Multiple Access (MIMO MC-CDMA) systems. At the transmitter, modified orthogonal transmit diversity (MOTD) encoders are used for increasing space and time transmission diversity. A P-way combiner is used to connect the MOTD encoders and P multi-carrier modulators. Each modulator is connected to a set of antennas. At the receiver, each multi-carrier demodulator has an amplitude/phase compensator to compensate distortion at every sub-carrier. Similarly, a combiner is used to connect the demodulators and the MOTD decoders. Upon the invention, the space, time, and frequency diversity can be explored.

Abstract: A communication system is disclosed that allows high data-rate transmission of data between components. N-bit parallel data is transmitted in K-frequency separated channels on the transmission medium so as to fully take advantage of the overall bandwidth of the transmission medium. Additionally, a cross-channel interference filter in a receiver section corrects for cross-channel interference in the communication system. As a result, a very high data-rate transmission can be accomplished with low data-bit transmission on individual channels. A transmitter system and a receiver system are described for the communication system.

Abstract: Single sideband (SSB) mixers and methods of extracting a SSB signal, which are capable of outputting a single frequency using a plurality of mixers and a local oscillating frequency without having to implement phase-shifting. In one embodiment, a single sideband (SSB) mixer comprises a first mixer and a second mixer, wherein the first and second mixers multiply an input IF (intermediate frequency) signal by a local IF signal having the same frequency of the input IF signal; a band-pass filter which passes upper sideband signal output from the first mixer; a third mixer which multiplies the upper sideband signals output from the band-pass filter by a LO (local oscillating) signal; a fourth mixer which multiplies the signals output from the second mixer by the LO signal; and a subtraction device that subtracts output signals of the third mixer from output signals of the fourth mixer.

Abstract: A time division duplex (TDD) single sideband (SSB) transceiver includes a transmitter adapted to input an analog audio signal, sample the analog audio signal, and to output an SSB frequency shift keyed (FSK) signal corresponding to the analog audio signal, the SSB FSK signal including analog information. A receiver is adapted to switch between receiving one of an upper sideband and a lower sideband of an external SSB signal.

Abstract: A chopper-direct-conversion (CDC) radio receiver includes a phase-alternating mixer receiving an antenna input signal and at least one local oscillator signal and generating a double sideband signal in a single mixing step. The phase-alternating mixer may be implemented by two parallel mixers each mixing the input signal with one of two local oscillator signals and an adder receiving and summing outputs from the two parallel mixers, by a track-and-hold circuit sampling the input signal based upon the local oscillator signal, or by a window averaging circuit averaging the input signal across a period of the local oscillator signal. The CDC architecture is suitable for fabrication on a single chip and offers solutions to virtually all problems found in conventional direct-conversion receivers.

Abstract: An SSB radio communication system and radio apparatus applicable to ultra high frequencies such as a VHF band and UHF band. In the transmitting side, a carrier wave is amplitude modulated by modulation input signals which comprise a constant amplitude, sine wave shaped reference pulse having a predetermined width and period and a sine wave shaped modulation pulse signal having an amplitude representing two- or multi-value digital values having the same width as the reference pulse signal and which are formed based on the amplitude of the reference pulse signal, and the modulated pulse signals are transmitted on a single side band, while in its receiving side the gain of received signals is automatically adjusted based on the reference pulse signal that is the value of the peak of the received signals.

Abstract: A transmitter upconverts a SSB data signal during a first operational mode using a RF upconverting signal having a frequency that is offset from a center frequency of a channel (?C) by an amount that depends on the data signal's SSB bandwidth (?M). In a second operational mode, the transmitter upconverts a tone signal having a frequency ?M using the same RF upconverting signal. The upconverted tone signal can be used as a continuous wave (CW) carrier signal having a frequency ?C. The transmitter has a single RF oscillator to output both a SSB signal centered at frequency ?C during the first mode and a carrier signal of frequency ?C during the second mode.

Abstract: The invention discloses a method that identifies whether a channel is LOS or NLOS in a mobile communication system. After coherent accumulation and non-coherent accumulation have been made by the system, first the method takes power difference between the direct path and the non-direct path in a same power delay profile to identify a channel; and then the result is further determined by {overscore (?)}/? difference of a LOS channel and a NLOS channel (where {overscore (?)} and ? is the mean delay and the RMS delay spread of a multipath power profile, respectively). A channel is determined as a LOS channel, if the power ratio of the Maximum Path to the Local Maximum Path is greater than a threshold K, and simultaneously the arrival time difference between the First Path and said Maximum Path is less than a time interval T; otherwise it is a NLOS channel. The method is easier to implement and compatible with the present mobile communication system.

Abstract: A discrete Fourier transform (DFT) filter bank with stack shift capability, configured, for example, as an analyzer, but equally applicable to a synthesizer, and implemented as a polyphase filter. The DFT filter bank includes a complex modulator for multiplying the input signals x0(m), x1(m) . . . xM?1(m) by a complex modulator e?2?ko(m). In order to keep the coefficients for the polyphase filter real, the coefficients are modulated by a DFT twiddle factor e?2?ko?/M. The use of the DFT twiddle factor enables the hardware to be reduced significantly. For example, for an 8 phase 203 tap filter, only 8 selectable negators are required as opposed to 211 for known DFT filter banks.

Abstract: A shaped-wave application section inputs a first pulse signal corresponding to transmission data output from a transmission data output section, and applies, to a modulation and amplification section, a signal wave corresponding to a second pulse signal such that the waveform of the first pulse signal is shaped. The pulse signal applied to the base of the transistor of the modulation and amplification section is amplitude-modulated into an amplitude-modulated wave in which the amplitude-modulated portion is strengthened, in accordance with the signal wave corresponding to the second pulse signal applied to the emitter thereof. The amplitude-modulated wave is supplied to an antenna section including a resonance circuit via the collector thereof, and is transmitted as an electromagnetic wave from the antenna section.

Abstract: An apparatus and method is disclosed for using adaptive algorithms to exploit sparsity in target weight vectors in an adaptive channel equalizer. An adaptive algorithm comprises a selected value of a prior and a selected value of a cost function. The present invention comprises algorithms adapted for calculating adaptive equalizer coefficients for sparse transmission channels. The present invention provides sparse algorithms in the form of a Sparse Least Mean Squares (LMS) algorithm and a Sparse Constant Modulus Algorithm (CMA) and a Sparse Decision Directed (DD) algorithm.

Abstract: A method and system for communication within an energy-transmission-limited environment. RF transceivers throughout the site are located site-wide such that areas within the site in which communications are desired are within range of at least one of the RF transceivers. At each location RF transceivers are connected to a control unit. The control unit provides power to the transceivers and allows bi-directional communication of audio/voice and/or digital information. The control units may be networked to each other using standard network type category-5 or equivalent cables and may communicate to one another via the network connection. The control units may also be networked via an alternating current powerline by using an alternating current modem. The transceiver of the present invention utilizes single sideband modulators to modulate voice and/or digital signals. The signals are demodulated and filtered at a receiving end of the transceiver. A comb filter attenuates noisy signals with drifting harmonics.

Abstract: In an AM system directed to commercial broadcasting, a pure unmodulated (CW) carrier signal and two sideband signals are generated and processed separately as three independent signals that are summed as output of a final linear mixer. The sideband signals are derived independently utilizing audio spectrum-sharing based on complementary comb filtering, quadrature phase-shifting at both audio and carrier sideband frequencies, and exclusive alternate toggling at a designated switching rate between the two sidebands so that at any instant in time only one of the two sidebands is present along with the continuous carrier. The overall performance provides the capability of advantageous modulation beyond the conventional 100% modulation limit.

Abstract: The present invention provides a method and device for determining the sideband ratio of a superconducting mixer using a comb generator. The method includes the steps of: (a) tentatively adjusting the sideband ratio of a mixer for calibration of an output of the comb generator; (b) determining the signal intensity of a pseudo-celestial signal oscillator for calibration of the output of the comb generator; (c) repeating the steps (a) and (b) to derive the relation between the sideband radio of the mixer for the comb-generator output calibration and the intensity of a pseudo-celestial signal; (d) calibrating the output of the comb generator; and (e) obtaining the sideband ratio of the mixer to be measured.

Abstract: A method for scrambling/descrambling an analog signal includes receiving an analog signal and converting the signal into an intermediate frequency signal. A Gaussian pseudo-random noise signal is generated and then multiplied with the intermediate frequency signal to scramble/descramble the received analog signal.

Abstract: An RF cable-less interconnect arrangement couples a diplexer to a radio transceiver by providing each of the transceiver and the diplexer by means of respective pairs of RF transmission and receiver channel connectors. The two sets of connectors are supported at a prescribed spatial separation for blind-mating RF connectivity for either of two orientations and translation (insertion) of the diplexer into the radio. Eliminating lossy and relatively fragile RF cable, that would otherwise occupy space within the radio's housing, and require installation by a skilled technician during assembly of the radio, allows the customer to easily change the radio's frequency plan by simply removing, rotating and reinserting the diplexer.

Abstract: A data delivery system uses a database containing a plurality of contents that can be delivered to the client devices at the requests of a client. Conventionally, data is “owned” by a user, that is, users have their own copies for the data. Such a method requires a large amount of, yet unnecessary, storage space. It is especially true when different users own the same data. A conventional technique, called reference counting, is used in programming where one memory data structure can be shared by multiple processes or other client data structures. Reference counting systems perform automatic memory management by keeping a count in each memory object of how many references there are to the object. Objects to which there are no references may be reclaimed. The reference count is incremented for each new reference, and is decremented if a reference is overwritten, or if the referring object is recycled. If a reference count falls to zero, then the object is no longer required and can be recycled.

Abstract: A receiver (10) for a wireless telecommunications system that provides relatively wideband signal processing of received signals without increased signal distortion so that multiple received signals can be simultaneously processed. The receiver (10) includes a specialized LNA (16), frequency down-converter (18) and ADC (20) to perform the wideband signal processing while maintaining receiver performance. The frequency down-converter (18) employs a suitable mixer (28), BPA (32), attenuator (34), and transformer (36) that are tuned to provide the desired frequency down-conversion and amplitude control over the desired wideband. The down-converter devices are selected depending on the particular performance criteria of the ADC (20). A specialized digital channelizer (22) is included in the receiver (10) that receives the digital signal from the ADC (20), and separates the signals into the multiple channels.

Abstract: A receiver (10) for a wireless telecommunications system that provides relatively wideband signal processing of received signals without increased signal distortion so that multiple received signals can be simultaneously processed. The receiver (10) includes a specialized LNA (16), frequency down-converter (18) and ADC (20) to perform the wideband signal processing while maintaining receiver performance. The frequency down-converter (18) employs a suitable mixer (28), BPA (32), attenuator (34), and transformer (36) that are tuned to provide the desired frequency down-conversion and amplitude control over the desired wideband. The down-converter devices are selected depending on the particular performance criteria of the ADC (20). A specialized digital channelizer (22) is included in the receiver (10) that receives the digital signal from the ADC (20), and separates the signals into the multiple channels.

Abstract: An FM broadcast transmitter transmits a broadcast signal having a carrier at a broadcast frequency and sidebands, able to be transmitted at full power, within a transmission band-width around the carrier. It includes a source of a modulated FM stereo signal having a carrier at the broadcast frequency and having sidebands with a bandwidth less than the transmission bandwidth representing a stereo signal. It also includes a source of a modulated IBOC signal, having carrier pulses spaced relative to each other to represent the IBOC digital data signal encoded as a variable pulse width encoded signal, and a bandwidth within the transmission bandwidth not overlapping the FM stereo signal sidebands. A signal combiner combines the modulated FM stereo signal and the modulated IBOC signal to form the broadcast signal.

Abstract: A vestigial-sideband (VSB) signal is down-converted to generate a VSB signal including a carrier frequency offset from zero frequency by an amount greater than the bandwidth of the VSB signal. The carrier of this final I-F signal has a carrier offset from zero-frequency, which carrier offset exceeds the highest modulating frequency of the VSB signal and is adjusted to a prescribed carrier offset value. The down-converted VSB signal is digitized to generate a digital multiplicand signal for a digital multiplier circuit. The digital multiplier circuit is supplied a digital multiplier signal descriptive of a system function composed of a constant term and a second harmonic of the carrier frequency offset from zero frequency. Digital product signal from the digital multiplier circuit is descriptive of a double-sideband amplitude-modulation final I-F signal in the digital regime, which DSB AM final I-F signal is subsequently detected to generate a baseband demodulation result.

Abstract: A tuning system and a tuning method in a broadcast signal receiver, in which a radio frequency (RF) spectrum signal adopting an inverting method is filtered by an asymmetric bandpass filter of a tuner to improve the receiving sensitivity. This tuning system includes a first mixer, a filter and a second mixer. The first mixer mixes a predetermined oscillation frequency with an inverted 8 VSB digital broadcast signal in the idle space between upper and lower normal NTSC broadcast signals of high frequency band received from a transmitter, transfers the upper NTSC broadcast signal to the lower side and the lower NTSC broadcast signal to the upper side, inverts the transferred NTSC broadcast signals, and changes the state of the 8 VSB digital broadcast signal into a normal state. The filter attenuates the inverted upper and lower NTSC broadcast signals output from the first mixer to a predetermined band and amplifies the normal 8 VSB digital broadcast signal into a predetermined band.

Abstract: The noise in a frequency demodulated audio signal is detected on basis of the characteristics of the stereo-multiplex signal to obtain a very reliable information that can be used for the sliding stereo-mono transition, noise blanking and a de-noising of the stereo-difference signal. A noise signal (vd,l(t)−vd,u(t) or vd,u(t)−vd,l(t)) is calculated by subtracting one sideband of the stereo-difference signal from the other sideband of the stereo-difference signal and as a direct measure for the quality of the signal generating the variance (&sgr;2vd) of the noise signal by squaring and thereafter averaging the noise signal.

Abstract: A receiver (10) for a wireless telecommunications system that provides relatively wideband signal processing of received signals without increased signal distortion so that multiple received signals can be simultaneously processed. The receiver (10) includes a specialized LNA (16), frequency down-converter (18) and ADC (20) to perform the wideband signal processing while maintaining receiver performance. The frequency down-converter (18) employs a suitable mixer (28), BPA (32), attenuator (34), and transformer (36) that are tuned to provide the desired frequency down-conversion and amplitude control over the desired wideband. The down-converter devices are selected depending on the particular performance criteria of the ADC (20). A specialized digital channelizer (22) is included in the receiver (10) that receives the digital signal from the ADC (20), and separates the signals into the multiple channels.

Abstract: Frequency synthesizers of a radio transceiver are automatically tuned so that its transmit and receive frequencies correspond to whichever upper band and lower band filters the radio transceiver has been connected by the user. A capacitive electrical impedance interface is coupled to filter circuitry of an upper band filter section, while an inductive electrical impedance interface is coupled to filter circuitry of the lower based filter section. A voltage reference circuit is coupled to one of the transmit port and the receive port of the transceiver. A controller is operative to automatically tune the transceiver to transmit in one of the upper and lower frequency bands, and to receive on the other frequency band, in accordance with the voltage level generated by the voltage reference circuit.

Abstract: A front end circuit for an RF dual band GSM/DCS phone includes a first channel including an elliptical high-pass filter, a first SAW filter, and a low noise amplifier and a second channel including a second SAW filter and a second low noise amplifier. The output of each channel is alternately switchable to a single-side band mixer circuit. This front end circuit arrangement provides significantly reduced cost and part count over other approaches.

Abstract: A method for decoding a suppressed-carrier modulated signal in the presence of a pilot tone, comprising the steps of:extracting the pilot signal from the modulated signal;obtaining the suppressed carrier by multiplying the pilot signal by the pilot signal in quadrature;adjusting the level of the suppressed carrier; andreconstructing the modulating signal.

Abstract: An SSB radio receiver having an inexpensive wide-band IF filter which passes through not only a reception objective SSB station IF signal but also an interference SSB station IF signal simultaneously. These signals are SSB-detected to reproduce the original modulating audio signals with a BFO frequency, the BFO frequency itself located out of the pass-band of the wide-band IF filter. The frequency of the reception objective SSB station IF signal is selected to be nearest to the BFO frequency, preferably at an end of the pass-band width of the IF filter. Frequency spectrums of the SSB-detected audio signals are separated by a frequency difference comprising the difference between the BFO signal and the IF signals. The SSB-detected audio signals are applied to a selected low-pass filter, such as an inexpensive active filter, having a pass-band which covers or passes only the SSB-detected audio signal of the reception objective SSB station IF signal.

Abstract: Disclosed is a procedure for filtering out the lower one of the upper other sideband of a double sideband oscillation consisting of a mix of several double sideband oscillations, the lower one and/or the upper other sideband of which is interfered with by the upper other, respectively the lower one by the upper other, respectively the lower one sideband turned toward it and partially overlapping, in telecommunication systems, in particular multi-channel telephone systems and short wave radio receivers. By means of mixing, demodulation and/or multiple mixing the interfering sidebands of the double sideband oscillation are brought into the frequency position of the interfered with sidebands and are canceled by adding with the opposite sign.