Abstract: In an apparatus, method, and system for reducing interference with an input signal to an FM receiver, a plurality of inputs are filtered by a first stage of filters. The outputs are received by an interference detector and further processed by a second filtering stage, an energy calculation stage, and a comparator stage. A switch, responsive to the outputs of the comparator stage, may output one of the first stage filter outputs based on a first set of comparator outputs and may output an interpolated value determined by the first stage filter outputs and based on a second set of comparator outputs.

Abstract: A received circuit receives a plurality signals generated by modulating carrier waves having the substantial same frequency according to digital signals having different bitrates output from a plurality of systems. The receiving circuit includes a front-end portion that tunes and outputs the signals received by an antenna; an analog-to-digital converting portion that converts the signals output from the front-end portion to digital signals; a signal processing portion that processes and demodulates the digital signals; and a plurality of digital filter portions each of which extracts a digital signal output from a corresponding system among the plurality of systems, from the demodulated signals output from the signal processing portion, based on a bitrate of the digital signal output from the corresponding system.

Abstract: An apparatus includes a filter module, an amplification module, and an adjustment signal source. The filter module generates a filtered signal based on a received signal. This filtered signal has a level shift corresponding to a difference between a direct current (DC) level of the filtered signal and a DC level of the received signal. From the filtered signal and an adjustment signal, the amplification module generates an amplified signal. The adjustment signal, which is provided by the adjustment signal source, may control (e.g., diminish) an effect of the level shift on a DC level of the amplified signal.

Abstract: The present invention relates to a device for receiving signals in a wireless cellular OFDM system, in which data symbols are transmitted in frequency subcarriers and timeslots. The present invention further relates to a method for channel estimation in such a device. According to the present invention, a channel estimation on the basis of received pilot symbols is performed, whereby the channel estimation for data symbols between pilot symbols is performed by means of a filter, said filter being selected from a set of filters on the basis of an interference reference value.

Abstract: An active step attenuator can attenuate the RF signal from a cable modem or other RF source. The active step attenuator converts the RF energy into a DC control signal that controls the attenuation applied to the RF signal. The voltage of the control signal is proportional to the RF energy, so that the active step attenuator attenuates a stronger RF signal more than a weaker RF signal. The active step attenuator may be in the form of a diplex circuit, one branch of which passes signals in one frequency band without attenuation and the other branch of which actively attenuates signals in another frequency band.

Abstract: According to an aspect of the present invention, there is provided with a device control system including: an acquiring unit which acquires a BML document which can be delivered in digital broadcasting; a BML interpreting unit which interprets a description described in the BML document, for controlling an external device; and a communication unit which communicates with the external device on the basis of a result of interpretation by the BML interpreting unit.

Abstract: A signal detector arranged in a receiver of a wireless communication device includes a variable passband bandpass filter configured to bandlimit a received signal using a variable passband; a signal parameter detection unit configured to detect a signal parameter of each of a plurality of signals contained in the received signal; a detection order determination unit configured to determine a detection order for detecting the signals from the received signal based on the signal parameter; a parameter control unit configured to control the passband of the variable passband bandpass filter based on the detection order and the signal parameter; and an equalization and decision unit configured to equalize and decide the bandlimited signal output from the variable passband bandpass filter. The signals contained in the received signal are successively detected from the received signal according to the detection order by means of the variable passband bandpass filter and the equalization and decision unit.

Abstract: An electrical circuit has at least two parallel signal paths connected to one another on the antenna side and for which a band reject filter corresponding to the transmission range is implemented in a second signal path for frequency-selective improvement of insertion loss in the transmission range of a first signal path. With a band reject filter, the signal is reflected to the junction of the parallel signal paths arising from the second signal path and thus is rerouted to the first signal path.

Abstract: A terminal data loading device on a mobile platform includes a media unit for receiving a transportable media element containing media data and outputting a media signal to a control processor unit. The control processor unit outputs an information signal to a wireline communication unit. The wireline communication unit outputs a wireline signal to a network on the mobile platform.

Abstract: A packet detector for a multi-band orthogonal frequency division multiplexing system includes a plurality of packet detection units each corresponding to a time frequency code for detecting packets according to a spreading sequence of the time frequency code, a comparison unit for comparing correlation values provided by division units of the plurality of packet detection units, and a packet decision module for determining a time frequency code and size of a fast Fourier transform sampling window according to output signals of the comparison unit, allowing a frequency band to be selected and synchronization to be executed.

Abstract: A reception device includes a number of reception paths and a decoder. The reception paths are sequenced and each reception path includes a calculation module embodied to deliver a combined confidence index and a combined data stream, from the confidence index and the equalized data stream for the current path, as well as, for the subsequent reception paths after the first path, from the combined confidence index and the combined data stream, for the preceding path. The decoder is embodied to only process the combined confidence index and the combined data stream, provided by the calculation module in the last path.

Abstract: A portable mobile communications device for controlling the destination of mobile TV programs broadcast by a mobile TV service provider includes a mobile TV device, a processor running a mobile TV redirect application communicable with the mobile TV service provider, and a user interface for controlling the mobile TV device and the mobile TV redirect application such that mobile TV broadcast programs can be simultaneously redirected to an external device in response to input received by the user interface and sent to the mobile TV service provider. The external device can include a home media server or a computer coupled to and communicable with the mobile TV service provider via the Internet.

Abstract: A technique for downconverting a RF signal comprises an antenna adapted to receive an RF signal; a transconductance amplifier connected to the antenna and adapted to amplify the RF signal; a passive mixer connected to the transconductance amplifier and adapted for current domain mixing of electrical current transferred from the transconductance amplifier; and a load impedance connected to the passive mixer. The load impedance may comprise a parallel combination of a frequency dependent negative resistance component, a capacitor, and a resistor. The load impedance may comprise a pair of complex poles, a pair of imaginary zeros, and a real pole. Voltages at an input and an output of the passive mixer are related such that the input voltage of the passive mixer is an upconverted version of the output voltage of the passive mixer, wherein the input voltage of the passive mixer is at an output of the transconductance amplifier.

Abstract: A digital down converter (DDC) can be provided in a digital radio receiver front end to produce baseband I and Q signals using mixing, decimating and narrow and wide filtering dependent upon the nature of the signals. After receiving a single wide IF signal from the IF tuner, a single IF ADC converts the IF signal to digital form, and the DDC generates wide and narrow baseband I and Q signals for digital signal processing. The DDC passes wide baseband I and Q signals to a digital baseband processor, while narrow baseband I and Q signals are passed to the analog baseband processor. The system and method of the present invention permits more accurate filtering of the respective digital and analog signals, while reducing receiver complexity and cost. An analog filter in the digital radio tuner can have relaxed specifications permitted by the DDC according to the present invention.

Abstract: A radio frequency transceiver having a printed circuit board (PCB) on which are located a plurality of components, the PCB being sandwiched between a base and a cover. The cover having a plurality of components for accommodating each of the plurality of components to separate the plurality of components into a number of virtual modules. All interconnects between the number of virtual modules are in the PCB. The PCB has a radio frequency (RF) layer, a RF ground layer, a direct current (DC) layer, and a DC ground layer. There is a plurality of via holes from the RF ground layer to the DC ground layer to provide virtual RF ground.

Abstract: A self-aligning resonator filter, a self-aligning coupled resonator filter circuit, and a television tuner circuit incorporating the filter and the circuit are disclosed herein. The self-aligning resonator filter leverages the local oscillator of the tuner circuit and can be realized with a significant reduction in the amount of off-chip components. The self-aligning resonator filter is configured to align its tunable resonator to resonate at a desired frequency in response to a phase difference measured across a resistance element during a tuning mode, and the resistance element is switched out of the self-aligning resonator filter during a run mode. The self-aligning coupled resonator filter circuit is configured to isolate its individual resonator stages during tuning such that each resonator stage can be aligned without being influenced by the other resonator stage.

Abstract: A method and apparatus are provided for a first controlled device, such as a wireless local transmitter that accepts a plurality of digital audio signals and corresponding program information signals converted from a controlled source, such as the encoded digital data provided by a digital data signal source, typically a community antenna television (CATV) cable or direct broadcast satellite, then modulates said digital audio and corresponding program information signals on different carrier frequencies and transmits the modulated signals to a plurality of second controlled devices, such as remote digital receiver/tuners that demodulate said signals to output music in stereophonic sound and display the corresponding program information by means of an alphanumeric display. The first and second controlled devices contain microprocessor systems for communicating, controlling, storing, processing, and display of digital data within the operation of the respective system.

Abstract: An adaptive electromagnetic wave canceling system and method for canceling an electromagnetic interference (EMI) signal generated from an EMI signal source, from a broadband signal being received by a receiver. In one implementation an adaptive canceller subsystem is used that directly receives the EMI signal and a sample of the broadband signal, in which the sample includes an EMI signal component. A time delay stage is incorporated to delay the broadband signal before it is received by the receiver. The adaptive canceller subsystem generates a correction signal that is an inverse of the EMI signal component. The correction signal is applied to the broadband signal to effectively cancel the EMI signal component therefrom before the broadband signal is received by the receiver. In one implementation an automatic gain control is implemented that automatically adjusts the adaptive canceller subsystem to a level of the sample broadband signal, to thus form a closed loop EMI canceling system.

Abstract: An antenna assembly includes a reflector dish and a unit attached at a distal end of an arm to receive satellite signals reflected from the reflector dish. The unit includes at least one low-noise block converter (LNB) to receive the satellite signals and a wireless communication transceiver that operates to transmit and receive video and data information within a surrounding range.

Abstract: A combined SAIC receiver and a multiple-antenna, receive diversity receiver are employed to reduce interference in a wireless system. The real and imaginary parts of the de-rotated signal for each receive path associated with an antenna are separately filtered and a combined output signal of all receive paths is generated. The weighting coefficients are adjusted based on an error signal produced by comparing the combined output signal with a reference signal. The weighting coefficients are initially set based on an MMSE/LS type of signal processing criteria, where the reference signal is the Training Sequence Code (TSC). Subsequent adjustment/tracking can be accomplished by using known tracking algorithms, e.g. LMS or RLS, or the coefficients can be re-computed using MMSE/LS processing. The reference signal for tracking may be a combination of the TSC and estimated data symbols provided by an equalizer.

Abstract: A comb-line wireless filter (5) includes an input end (505a), an output end (505b), a first transmission line (501b), a second and third transmission line (501a, 501c) each having a curved shape, and a first, second, and third capacitor (503b, 503a, 503c). The first transmission line has a first transmission line part and a second transmission line part. The second transmission line and the third transmission line are separately on the two sides of the first transmission line part of the first transmission line. The input end and the output end are separately connected to first ends of the second transmission line and the third transmission line. The capacitors are separately connected to first ends of the transmission lines. According to the curved shape of the second transmission line and the third transmission line, the size of the comb-line wireless filter is significantly reduced.

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: A network terminal apparatus in a type of directly connecting to a packet communication network, with an interface for connecting to a circuit under an environment of an SIP terminal network, and a capability of carrying out facsimile transmission/reception, carries out a call control method according to SIP, transmits and receives an SDP added to a message body of an SIP, and carries out, in a same session, both a call control session transmitting and receiving an SIP message and an SDP and a T.38 session transmitting and receiving a T.38 signal.

Abstract: An adjacent interference removal device capable of providing an improved reception quality. An IF signal Sin having passed through an IF filter having a pass frequency band width of 200 kHz is supplied to a first narrow band filter having a pass frequency band width extending from a center frequency (carrier frequency) of the IF filter to +50 kHz, as well as to a second narrow band filter having a pass frequency band width extending from a center frequency (carrier frequency) of the IF filter to ?50 kHz.

Abstract: A mobile wireless communications device includes a housing and circuit board carried by the housing. Radio frequency (RF) circuitry carried by the circuit board forms a transmitter and receiver. A processor is carried by the circuit board and operative with the RF circuitry. A keyboard connector is mounted on the circuit board. A plurality of Key_Out and Key_In connection lines are carried by the circuit board and connect the keyboard connector and processor. A keypad is carried by the housing and operatively connected to the keyboard connector. A filter is operative with each connection line for limiting degradation in receiver sensitivity.

Abstract: Disclosed is a mobile communication terminal which is provided with an equalizer function of audio equipment to adjust a timbre of transmitting/received speech sounds so as to satisfy a great number of users having various individualities and tastes simultaneously. The mobile communication terminal according to the present invention includes an equalizer connected to a CODEC, a speaker and a microphone for adjusting a timbre of an analog speech signal inputted thereto from the CODEC and/or a speech signal inputted thereto through the microphone, and an equalizer control circuit for controlling a timbre control operation of the equalizer according to a control signal of a CPU.

Abstract: A method for influencing, e.g., for decreasing, the treble reproduction of an audio signal for reproduction obtained from a received signal, the received field strength and reception quality of the received signal being evaluated and, as a function thereof, the transfer function of at least one filter unit that can be impinged upon by the audio signal being controlled, as well as a circuit assemblage or arrangement for performing such a method for the modification of treble reproduction, so that, among other things, reproduction of the interference may always be reliably concealed and so that no noticeable and/or irritating “flutter” effects may occur. The method may include processing of the output signals of at least two reception interference detectors, and processing of the received field strength may be accomplished respectively in at least one first processing branch operating at a first, e.g.

Abstract: An architecture for a receiver front end utilizes a dual output low noise amplifier (102) driving separate, fixed preselectors (104, 106) coupled to a transformer (108) to generate a single ended output (113). A pair of blocks coupled in series provides a dual band output. Additional pairs of blocks (201, 203) can be cascaded in parallel to provide additional frequency bands of operation. The front end architecture of the present invention provides switchless multi-band operation to a communication device.

Abstract: An amplification system for reducing DC offset in an input signal uses a low pass filter to isolate a DC component of the input signal. The system then subtracts the DC component from the input signal. In one embodiment, the system includes first and second amplifiers in addition to the low pass filter. The first amplifier amplifies the input signal to generate a first amplified signal at a differential output port of the amplification system. The second amplifier amplifies a low pass filtered version of the input signal to generate a second amplified signal at the differential output port of the amplification system. The outputs of the first and second amplifiers are connected to the differential output port of the amplification system in such a way that the first and second signals combine 180 degrees out of phase at the output port.

Abstract: A communication system includes a front-end multi-throw switch, a back-end multi-throw switch, multiple filters and a switch controller. The front-end multi-throw switch includes front-end throws and a front-end pole. The front-end pole is coupled to a receive channel or a transmit channel. The front-end pole is switchably coupled to one of the front-end throws. The back-end multi-throw switch includes back-end throws and a back-end pole. Each of the back-end throws is associated with a corresponding one of the front-end throws. The back-end pole is coupled to the receive channel or the transmit channel. The back-end pole is switchably coupled to one of the back-end throws. The one of the back-end throws corresponds to the one of the front-end throws. The filters are interposed between the front-end multi-throw switch and the back-end multi-throw switch. Each of the filters has a first port coupled to one of the front-end throws and a second port coupled to one of the back-end throws.

Abstract: A high frequency device includes a transmission/reception amplifier 13 that amplifies and outputs an input signal, and a transmission/reception switch 2 that gang switches internally so that during transmission an input of the transmission/reception amplifier 13 is connected to an up mixer and an output of the transmission/reception amplifier 13 is connected to an antenna unit 5, and so that during reception the output of the transmission/reception amplifier 13 is connected to a down mixer and the input of the transmission/reception amplifier 13 is connected to the antenna unit 5.

Abstract: An adaptive receiver is disclosed for optimally receiving and processing signals. The receiver utilizes one or more memory blocks to store groups of incoming symbols. The groups of symbols are processed by a channel estimation subsystem to determine channel characteristics. The receiver determines the appropriate demodulation and decoding strategy to implement based on the determined channel characteristics. The receiver includes a plurality of demodulation and decoding schemes, one of which is selected based on the results of a channel estimation analysis.

Abstract: A system (10) and method (100) for digitizing a complete band of RF channels to allow simultaneous processing of more than one channel. Multiple tunable bandpass filters (14) are used for the particular channels to be processed. The filter outputs are combined (16) to form one signal for digitization (18). In another embodiment, an undesired signal is rejected (112) to provide more available power for a reception of a desired signal.

Abstract: A frequency mixer that generates out of phase sum signals and uses the out of phase relationship to absorb sum signal energy in an energy absorbing component. A frequency mixer according to the present teachings includes a set of mixing devices that generate a first sum signal and a second sum signal in response to an input signal and a drive signal such that the first sum signal is out of phase in relation to the second sum signal. A frequency mixer according to the present teachings includes an energy absorbing component that absorbs the out of phase sum terms from the mixing devices.

Abstract: A band edge amplitude reduction system changes the filtering characteristics of a receiver based on the amplitude of signal(s) adjacent to an edge of the operating band of the receiver and/or of signals not under the power control of the receiver. For example, the receiver measures the power level over a bandwidth at the band edges of the operating band of the receiver. If the signals adjacent to the operating band are strong enough relative to the signal power within the operating band, overload protection circuitry changes the filtering characteristics of the receiver to improve the attenuation of the signal(s) from the adjacent band(s). In certain embodiments, the overload protection circuitry switches in filter(s) with a narrower bandwidth to attenuate the signal(s) from adjacent band(s) at the edge(s) of the operating band of the receiver, thereby preventing interference with or the overload of the receiver by signals from outside the operating band and/or not under the power control of the receiver.

Abstract: A channel estimation apparatus for WCDMA mobile communication terminal is disclosed. The channel estimation apparatus includes a moving average filter for calculating the average value of pilot signals; an interpolator for computing a tentative estimation value of channel variation by using linear interpolation algorithms based on the average value of pilot signal; a channel compensator for compensating a channel variable of the data signal delayed in a predetermined time based on the tentative estimation value of channel variation; a decision block unit for tentatively determining data signal based on the compensated data signals; a raw channel estimator for computing a raw channel estimation value based on the output signal of the decision block unit and the data signal delayed; and a non-linear filter for computing a final channel estimation value of channel variation based on the tentative estimation value of channel variation and the raw channel estimation value.

Abstract: A method of frequency estimation for a GSM communications system is disclosed. First, the a frequency control channel data burst is received and downsampled into a plurality of subsets. Then, the subsets are filtered using an auto-regressive filter. The filtered subsets are then correlated and summed to determine a parameter r. The estimated frequency is calculated based upon the parameter r.

Abstract: A multi-channel filtering system for use with a transceiver includes a front-end multi-pole, multi-throw switch, a back-end multi-pole, multi-throw switch, and a plurality of filters. The front-end switch includes a receive pole, a transmit pole, and a plurality of switch throws. The back-end switch also includes a receive pole, a transmit pole, and a plurality of switch throws. Each of the plurality of filters has first and second ports, each first port coupled to one of the switch throws of the front-end switch, and each second port coupled to one of the switch throws of the back-end switch. Using this configuration, filters of differing bandwidths can be switched in during signal reception and/or transmission, thereby tailoring the communication rate to the particular conditions.

Abstract: A method of, and receiver for, countering distortions in radio channels due to intersymbol interference (ISI) and other non-linearities in a radio link, comprises a first equalizer (48) using a training sequence for equalizing one type of distortion, say that due to ISI, and a second equalizer (50) coupled to recieve the equalizing output of the first equalizer and using another training sequence for equalizing another type of distortion. The first and second equalizers may be fractionally spaced equalizers.

Abstract: A communication filter circuit useful in a dual-mode receiver comprises a cascade of an active twin-T filter and a passive twin-T filter sections defining sharp notches at the center of second adjacent and of third adjacent channels, respectively, and specifically providing most attenuation at 60 kHz and at 90 kHz, for operation in the ISM136 band which has 30 kHz channel spacing. Since communication is channelized and limited in bandwidth, an active/passive twin-T notch filter structure is effective for signal attenuation. In a circuit in which real and imaginary signal components are processed, active-passive twin-T filters are provided in each of four signal paths, namely I and ?I, Q and ?Q.

Abstract: First and second transmission paths P1 and P2 are disposed between a first port #1 connected to an antenna ANT and a second port #2 connected to a transceiving circuit 10. The first transmission path P1 includes receiving filters Rx1, Rx2, and Rx2?, an amplification circuit LNA, and 90° hybrid circuits 12 and 14. The second transmission path P2 includes a transmitting filter Tx1. A received signal amplified by the amplification circuit LNA is transmitted to the port #2 via the 90° hybrid circuits 12 and 14, but is not transmitted to the second transmission path P2. A transmission signal is transmitted from the port #2 to the second transmission path P2. This prevents oscillation of the received signal due to positive feedback.

Abstract: A method and apparatus for determining the data rate of a reverse link communication of an access terminal includes receiving a reverse activity bit (RAB) from an access point in the communication system, and passing the RAB to a digital filter to produce a filtered RAB. In one embodiment, the reverse link data rate is determined based on the filtered value of the RAB. Furthermore, a processor in the access terminal may determine whether the access terminal is in an idle mode, and passing a non-busy state value of the RAB to the digital filter when the access terminal is in the idle mode. The filtered RAB may be compared to a threshold to determine a mode of reverse link data rate determination. The mode defines a set of criteria for an aggressiveness level of increasing or decreasing the reverse link communication data rate. The processor, therefore, determines the data rate based on the filtered reverse activity bit in accordance with the determined mode.

Abstract: An apparatus comprising a first circuit, a second circuit and a third circuit. The first circuit may be configured to filter an analog input signal in an analog domain in response to one or more control signals. The second circuit may be configured to convert the analog input signal to a digital signal. The third circuit may be configured to generate the control signals in response to the digital signal. The third circuit may also be configured to control skewing of the analog input signal within the first circuit to partially compensate for frequency dependent effects associated with a transmission medium.

Abstract: An AM neighboring interference removing method and circuit is provided which can select only a desired AM modulation wave even if an interference AM modulation wave is partially superposed upon the desired AM modulation wave. An AM modulation wave desired to be received is multiplied at multipliers by local oscillation signals having frequencies 3fc/2 and fc/2 where fc is the carrier frequency of a neighboring interference AM modulation wave. High frequency components contained in the outputs of the multipliers are removed by low-pass filters. Of the outputs of the low-pass filters, the carrier frequency of the neighboring interference wave is fc/2 and the AM carrier frequencies of the AM stereo modulation wave are (fc/2+f?) and (fc/2?f?), where f? is a difference frequency between the AM carrier frequency of the AM stereo modulation wave and the carrier frequency of the neighboring interference wave.

Abstract: A Method for filter tuning using direct digital sub-sampling is provided. The tuning is accomplished in the digital domain by determining the filter characteristics from the shape of the transfer function. The input signal (1) is passed through the filter (3) and is then sub-sampled by and Analog-to-digital Converter (ADC) (5). The sub-sampled signal (6) is then processed in the digital domain using a digital circuit (7) that is used to determine the center frequency (Fc) and Quality factor (Q) and/or other important filter parameters. The Fc, Q and/or other important filter parameters are then adjusted by generating digital control signals (8) that can be converted to analog signals (10) using Digital-to-analog Converters (DACs) (9).

Abstract: The invention relates to the filtering of a subfrequency band out of a receive frequency band, in which a carrier frequency for prefiltering the receive frequency band and an intermediate frequency for demodulating the frequency band filtered out during the prefiltering and for generating a frequency baseband are inserted into the signal propagation path, in which the desired subfrequency band is filtered out of the frequency baseband by a post-filtering and in which the carrier frequency, the intermediate frequency and the post-filtering are matched to one another.

Abstract: This invention is applied to dual mode provided receiver capable of coinciding with both TDMA system and the non-TDMA system so as to provide a DC offset cancel circuit preferable for each communication method having a compact structure. In case where a predetermined time slot is allocated as an offset quantity detection time in the TDMA system, a first feedback loop is activated and corresponding to detection signals corresponding to differential output signals OUT, XOUT by a comparator 2, a detection result is updated in the holding section 3 according to a strobe signal STB and held therein. Output signals from the holding section 3 are fed back to an amplifier 1 through a selection section 5 and a DC offset is cancelled out.

Abstract: A system handles both reception signals collected via an antenna and transmission signals generated by a communication station for transmission via the antenna. The system includes a cryostat, a receive path carrying the reception signals and disposed in the cryostat, and a transmit path carrying the transmission signals. The receive path and the transmit path are coupled between the system and the antenna and between the system and the communication station. Accordingly, the receive path is duplexed with the transmit path such that the front-end system has a first single input/output connection for coupling the front-end system to the antenna and a second single input/output connection for coupling the front-end system to the communication station.

Abstract: A radio receiver (100) has an IF (intermediate frequency) filter (200) for automatically adjusting its intermediate frequency. The filter (200) includes a filter bank (304), an accumulative sub-band formation (322) and an accumulative sub-band power estimator/switch control (324). The filter bank (304) generates sub-bands, each sub-band having a predetermined frequency range. The accumulative sub-band formation (322) selectively sums the sub-bands to provide lowpass filters having incrementally increasing bandwidth. Power estimates of the lowpass filters are used to determine which lowpass filter output is appropriate for adjacent station interference. Also, if there is no adjacent station interference, the IF filter (200) selects the appropriate filter output depending on the signal strength of the desired station.

Abstract: The transmission system according to the invention comprises a transmitter (10) and a receiver (12). The transmitter (10) can transmit a signal (11) to the receiver (12). The receiver (12) comprises an interference absorption circuit (20) for detecting interference components included in the signal (11) and for substantially removing, during a time interval (?t), the interference components from the signal (11). The interference absorption circuit (20) is arranged for adapting the time interval (?t) in dependence on the duration of the individual interference components. Preferably, the time interval (?t) is substantially equal to the duration of the individual interference components. In this way, despite the fact that the interference components have a variable duration, the interference components can be accurately removed from the desired signal (11).