Abstract: An booster/amplifier receives a plurality of RF signals, including a subject RF signal. A location-based signal spectrum is determined by performing either a frequency scan or an information lookup operation. An initial filter bandwidth for the booster/amplifier is set based at least in part on the determined signal spectrum and a target time delay interference. In one embodiment, the initial filter bandwidth is set such that both the TDI and ACI are optimized/minimized. The initial filter bandwidth subsequently may be adjusted from its initial value based on actual measured ACI and/or TDI values.

Abstract: The communication performance of a radio communication system is improved while keeping short time necessary for attaining synchronization. A low noise amplifier is selectively provided with one of an input signal supplied from the outside of the system and an oscillation output signal of a local oscillator. A mixer integrates the oscillation output signal of the local oscillator and an output signal of the low noise amplifier. An intensity discriminating unit discriminates the signal intensity of an output of the mixer. In a first state, the low noise amplifier amplifies the oscillation output signal of the local oscillator, and a control unit learns a frequency band of the low noise amplifier for maximizing the signal intensity on the basis of the discrimination result of the intensity discriminating unit. In a second state, the low noise amplifier is set to the frequency band learned in the first state and amplifies the input signal.

Abstract: A system for processing a signal comprises a Radio Frequency (RF) signal tuner, one or more filters in a signal path of the RF tuner each based on Inductive/Capacitive (LC) circuitry, a variation unit operable to measure a variation of the LC circuitry, and a frequency control unit adapted to adjust the one or more filters based on the LC variation during operation of the tuner.

Abstract: Methods and systems for programmable baseband filters supporting auto-calibration in a mobile digital cellular television environment are provided. Aspects of the method may include generating within a single-chip multi-band RF receiver, at least one control signal based on signal strength of a baseband frequency signal generated within the single-chip multi-band RF receiver. A bandwidth of a filter integrated within the single-chip multi-band RF receiver may be adjusted via the generated at least one control signal. The filter may be used for filtering the generated baseband frequency signal. A frequency response signal of the filter integrated within the single-chip multi-band RF receiver may be determined via a reference frequency signal. An attenuated reference frequency signal may be generated by attenuating the reference frequency signal. The attenuated reference frequency signal may be compared with the frequency response signal. The at least one control signal may be generated based on the comparison.

Abstract: A communication system with variable filter bandwidth includes a first mixer circuit configured to receive a communication signal and shift the frequency range of the communication signal to a first frequency range. A second mixer circuit is configured to receive the same communication signal and shift the frequency range of the communication signal to a second frequency range. An activation circuit is coupled to the first and second mixer circuit so as to provide an activation signal that activates at least one of the mixer circuits. A plurality of filter circuits are provided such that each filter circuit is configured to receive a signal from a corresponding mixer circuit, when said corresponding mixer circuit is activated.

Abstract: Described is a method for detecting activity on a frequency band. A wireless signal of a predetermined radio frequency band is received. The signal is processed into a plurality of subsignals, each subsignal corresponding to a particular radio frequency channel of the band. An energy level of the corresponding subsignal is determined, and, when the energy level is greater than a predetermined level, the corresponding channel is analyzed.

Abstract: A system and method for detecting the presence of a signal on a channel mixes signals received with an antenna with a local signal having a controllable frequency within a band of frequencies defined by the channel. The local signal is produced with a sequentially adjusted frequency within the channel. The mixing operation (for each local signal frequency) produces an output signal having a frequency indicative of a difference between a frequency of signals received with the antenna and a frequency of the local signal. The output signal is converted to a baseband frequency band, and is then analyzed to determine whether the signals received with the antenna occupy the channel.

Abstract: The present invention provides a movie channel to a user on a mobile device. Movie based content associated with a movie channel is automatically delivered and stored on a mobile electronic device for access by a user. Using the device, users can quickly and efficiently access movie information without having to type in information, or specifically request the movie information to be downloaded to the device. The movie channel includes several different modes for categorically displaying different types of movie information. Some example modes include: a movies mode; a theaters mode; and a current top movies mode. The movies mode is organized to display information relating to particular movies on the electronic device. The theaters mode is arranged to display information relating to particular theaters on the electronic device. The current top movies mode displays information relating to the current “hot” movies.

Abstract: According to a disclosed method, a calibration signal is provided at a first frequency corresponding to a low frequency edge of a desired passband to an input of a filter (240). A first value is measured at an output of the filter (240). The calibration signal is provided at a second frequency corresponding to a high frequency edge of the desired passband to the input of the filter (240). A second value is measured at the output of the filter (240). The first value is compared to the second value. A characteristic of the filter (240) is changed in response to the comparing. In one form, the filter is an IF filter (240) and a receiver (200) includes both the IF filter (240) and a calibration circuit (250) for forming the calibration signal and providing the calibration signal to the IF filter to change the characteristic in response to a calibration operation.

Abstract: A method for power control in an ultra wideband impulse radio system includes: (a) transmitting an impulse radio signal from a first transceiver, (b) receiving the impulse radio signal at a second transceiver; (c) determining at least one performance measurement of the received impulse radio signal; and (d) controlling output power of at least one of the first transceiver and the second transceiver in accordance with the at least one performance measurement.

Abstract: A method and apparatus for detecting a frequency band and mode of operation using recursive sampling and narrowing down is disclosed. The method comprises sampling (215) by a multi-mode wireless communication device, a broad operational frequency spectrum at a first sampling rate to produce a first set of discrete signal samples. Then, the wireless communication device compares (230, 240) at least one of the energy graphs of the first set of discrete signal samples with at least one protocol-specific signature to confirm (245), if an approximate match is found. When one or more approximate matches are found, the wireless communication device narrows down (250) the broad frequency spectrum to a reduced set of frequency band(s) that correspond to the matched protocol-specific signature(s). Then the steps of sampling (215), comparing (230, 240), confirming (245), and narrowing down (250) are recursively followed till a frequency band and mode of operation is confirmed.

Abstract: An amplifier has a band pass response. The band pass response may be set by setting corner frequencies of low pass filters.

Abstract: An adaptive band-pass filter for a wireless receiver comprises a band-pass filter associated with the receiver, the band-pass filter configured to selectively filter the received signal, and a switch responsive to a control signal, the switch configured to control the band-pass filter based on a level of the received signal.

Abstract: In a method of tuning a receiver for a digital signal (MPEG2-TS), an input signal (RF-in) is filtered (In-filt, Band-filt) to obtain a processed signal, a digital figure of merit (BER) is determined (Mix/Osc/IF amp IF-downconv-2, C) from the processed signal, and the filtering step (In-filt, Band-filt) is fine-adjusted (?P, PLL, DAC1-DAC3) in dependence on the digital figure of merit (BER).

Abstract: An object of the invention is to provide a receiving circuit where the quality of reception can be prevented from deteriorating when the gain changes, so that the good quality of the received signal can be preserved, as well as a receiving apparatus and a transmitting/receiving apparatus using the receiving circuit. In the configuration of the invention, a switch (113) is converted to a short state in response to a change in the gain of a variable gain amplifier (107) by means of a gain control apparatus 112, and thereby, the output terminal of a high pass filter (111) is fixed at a reference voltage and the cutoff frequency of a low pass filter (108) is increased. As a result, the period during which the DC voltage has transient response properties in the low pass filter (108) can be shortened, and this transient response prevented from passing through the high pass filter (111).

Abstract: A signal filtering system for a frequency reuse system. A first implementation may include a downlink baseband signal, coupled to a downlink bandwidth filter, including a composite received signal including at least an interfering signal and a signal of interest, each having a composite bandwidth, a first bandwidth, and a second bandwidth, respectively. An uplink baseband signal may be included, coupled to an uplink bandwidth filter, having a replica of the interfering signal corresponding with the interfering signal and having an interference bandwidth. A baseband processing module may be coupled with the downlink bandwidth filter and the uplink bandwidth filter and may be configured to cancel the interfering signal from the composite received signal using the replica of the interfering signal. The downlink bandwidth filter may be configured to reduce the composite bandwidth and the uplink bandwidth filter may be configured to reduce the interference bandwidth.

Abstract: Embodiments of the present invention include circuits and methods for reducing DC Offset. In one embodiment the present invention includes storing DC offset on internal capacitances. In one embodiment, parallel stages are used to remove DC offset corresponding to different local oscillator frequencies. Embodiments of the invention further include changing the low cutoff frequency of the DC cancellation circuits for fast calibration. In a first state, a high pass filter may have a first low cutoff frequency, and in a second state the high pass filter may have a second cutoff frequency lower than the first low cutoff frequency. The present invention also includes a variable gain amplifier with reduced DC offset.

Abstract: A method and implementation disclosed for detecting interference. A state machine controller is provided for establishing an interference detection cycle including a power sample period and a periodic sampling interval. A receiver component, responsive to the state machine controller, performs an energy measurement at a predetermined wireless band during the power sample period. A threshold comparator determines whether the energy measurement exceeds a predetermined threshold. A processing implementation processes the energy measurement to determine whether it corresponds to interference on the predetermined wireless band, if the measurement exceeds the predetermined threshold. A deactivating implementation is used to instruct the state machine controller to await the next power sample period, if the energy measurement does not exceed the predetermined threshold.

Abstract: A scaled input current is produced that substantially matches the full scale input of a CT??ADC that substantially cancels an offset bias current component of the input current. A bias resistance value is coupled between the integrator input and one of a supply voltage and a circuit common. Generally, the system is operable to produce digital data based on the filtered IF signals based on an analog feedback signal and upon an offset compensation signal wherein the analog feedback signal is based upon the digital data. Offset compensation logic is operable to detect an amount of DC offset in a digital IF demodulated digital serial data and producing the offset compensation control signal based upon the detected amount of DC. A programmable bias current is operable to substantially cancel a bias voltage component of the received analog feedback signal based upon an offset compensation control signal.

Abstract: A method and apparatus of calibrating filtering of receive and transmit signals is disclosed. The method of calibrating filtering of a received signal includes injecting an LO signal. The injected LO signal is filtered by a tunable filter. The filtered signal is frequency down-converted with an equivalent LO signal. The frequency down-converted signal is sampled while tuning the filtering. A desired filter tuning is determined based upon the samples and a frequency of the LO signal. The method of calibrating filtering of a transmit signal includes injecting an LO signal to a transmitter. The LO signal is filtered by a tunable filter. The filtered signal is frequency down-converted with an equivalent LO signal. The frequency down-converted signal is sampled while tuning the filter. A desired filter tuning is determined based upon the samples and a frequency of the LO signal.

Abstract: The present invention provides a method and an apparatus for controlling a communications system that includes a mobile wireless device, a first and a second base station and a radio network controller. The communications system may allocate frequency bands to users on a multiplicity of channels associated with a multi-layer access network across at least two cells communicatively coupled to a first and a second base station, respectively. The method comprises monitoring a radio emission parameter associated with the first and second base stations that communicate with the mobile wireless device. A radio emission parameter associated with the first and second base stations, such as signal strength or quality, is monitored, to select a target cell among a set of candidate cells for the mobile wireless device and to transfer the mobile wireless device from a first frequency band to a second frequency band.

Abstract: A method and apparatus for channel estimation in a rake receiver of a CDMA communication system operates with a finite-impulse-response channel estimation filter with L taps and having a fixed delay. A pilot sequence of a received sequence of data from a channel of the communication system on the rake receiver is input. A quality of the channel of the communication system is determined using noise or Doppler measurements. These measurements are used in adjusting a bandwidth of the filter to accommodate the channel quality while keeping the fixed delay, which minimizes the delay buffer size. The filter is then used to operate on the received sequence of data to provide coherent modulation.

Abstract: A tuning method comprises: detecting a fundamental intermediate frequency IF0 of a channel to be received; determining whether the fundamental intermediate frequency IF0 is affected by an adjacent channel; when the fundamental intermediate frequency IF0 is affected by the adjacent channel, detecting a tuning intermediate frequency that is not affected by the adjacent channel while changing the fundamental intermediate frequency IF0; when there is no variable intermediate frequency that is not affected by the adjacent channel, detecting a variable intermediate frequency that is least affected by the adjacent channel as the tuning intermediate frequency; and tuning the channel using the tuning intermediate frequency.

Abstract: A method for processing signals received (30) by a sound programme signal receiver includes a step (42, 44) of adjusting at least one parameter for processing small audio signals obtained from the received signals. It further includes a prior step of dividing a space representing a quality of reception of sound programme signals into a plurality of reception zones wherein the sound programme signal receiver is likely to be located. The adjustment (42, 44) of the parameter for processing small audio signals is determined on the basis of one of the reception zones wherein the sound programme signal receiver is located.

Abstract: Methods and apparatus for implementing a multi-carrier communications system are described. Various approaches to a phased system deployment and system configurations resulting from different levels of deployment are described. In addition mobile node and methods of operating mobile nodes in communications systems that may have different levels of deployment in different cells are described.

Abstract: A signal reception apparatus and method for communication systems. The signal reception apparatus for communication systems according to the present invention is applicable to communication environments in which a plurality of sub-bands having different frequency bands are sequentially used for communications. An embodiment of the invention has a multi-band index generation unit, a multi-band frequency generation unit, a multiplication unit, a correlation signal reception unit, and a buffer unit. The multi-band index generation unit generates a multi-band index corresponding to a sub-band to which a received signal is transmitted in correspondence with the multi-band index. The multiplication unit outputs a signal obtained by multiplying the received signal by the multi-band frequency. The correlation signal reception unit integrates and outputs the signal of the multiplication unit based on an integral time set in correspondence with the multi-band index.

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: An apparatus including automatic gain control (AGC) includes at least one variable gain amplifier (VGA) operative to receive an input signal and to generate an amplified signal. A gain of the VGA is controlled as a function of at least a first control signal. The apparatus further includes an AGC circuit coupled to the VGA and being operative to generate the first control signal. The AGC circuit has a bandwidth that is controlled as a function of at least the amplified signal and a second control signal, the second control signal being indicative of a motion of the apparatus.

Abstract: A digital tuning system (250) for changing a cutoff frequency of an analog filter (132) includes digital synthesizers (292 and 294) for producing a two-tone calibration signal (196) applied to an input of the filter after a quality factor of the filter is increased. The filter includes at least one R/C circuit with two resistors (304 and 306) for changing the quality factor and arrays (308 and 310) of capacitors for changing the cutoff frequency. The amplitude of the magnitude responses (409 and 411) of the filter to each tone (405 and 407) is measured by a two discrete Fourier transform single-frequency bin power detection circuits (253 and 254) while the filter is sequenced through a plurality of capacitance settings. An optimal capacitance for the R/C circuit is selected by comparing, to a pre-selected value, a difference between the responses of the filter to each tone, for each capacitance setting.

Abstract: Disclosed is a high frequency apparatus which eliminates an influence of interfering signals. An interference-cut filter (24) for eliminating interfering signals is disposed between an input terminal (22) and a mixer (27). The interference-cut filter (24) is so controlled that it effectively demonstrates the function while the interfering signals are transmitted. Control of the interference-cut filter (24) is made by a switch (23), which is controlled by a selector switch controller (39), and the switch controller (39) is controlled responsive to an error correction counter (38) and a radio wave transmitted from a cellular telephone (40). This structure eliminates interference attributable to communication signals transmitted by the cellular telephone (40) and undesirable signals entering from the outside. The invention can thus realize high quality reception.

Abstract: A wireless communication device comprises a plurality of receive signal paths, each of the receive signal paths is configured to receive signals in a certain frequency bandwidth. The communication device also comprises an amplifier coupled with each of the plurality of receive signal paths. The amplifier is configured to amplify the receive signals associated with each of the plurality of receive signal paths.

Abstract: A radio frequency (RF) tuner includes a programmable tracking filter bank receiving an RF input and outputting a filtered RF signal. A mixer stage receives the filtered RF signal and outputs a first quadrature component of the filtered RF signal and a second quadrature component of the filtered RF signal. Two variable gain amplifiers receive the first and second quadrature components and output amplitude-controlled I and Q components of the filtered RF signal. In one embodiment, the programmable tracking filter bank includes a plurality of tank circuits each connected to the RF input through an impedance. Each tank circuit include an inductor and a capacitor connected in parallel thereby forming an LC network, and a plurality of switched capacitors in parallel with the LC network and switched in and out of the tank circuit by programmable switches. In another embodiment, the programmable tracking filter bank includes a plurality of peaked low-pass circuits each connected to the RF input through an impedance.

Abstract: A bandpass-sampling analog-to-digital demodulator (BS-ADD) is provided. A radio frequency (RF) signal is received by a junction summer, which subtracts a feedback signal from the RF signal to produce an error signal. The error signal is then bandpassed and amplified by the RF bandpass filter/amplifier. The amplified signal is bandpass-sampled by a low-resolution analog-to-digital converter, and is demodulated and converted into a high-resolution digital signal. The down converted signal is multiplied with a clock to be up-converted back to the radio frequency. The resulting multiplied signal is converted to an analog signal and fed back to the junction summer.

Abstract: A method and apparatus for power conservation is provided for a multi-mode wireless communication device (100) capable of operating in a plurality of networks, each of the plurality of networks having a network signal with predetermined spectral characteristics. The wireless communication device (100) includes a variable bandwidth signal detector (140), a threshold detector (145), and a controller (120). The variable bandwidth signal detector (140) receives radio frequency (RF) signals and defines a detection bandwidth for signal detection. The threshold detector (145) is coupled to the variable bandwidth signal detector (140) and detects a network signal within the RF signals in response to determining whether a signal is present within the detection bandwidth having a signal strength greater than a predetermined signal strength.

Abstract: Various embodiments of the present invention adjust an operating mode of a configurable receiver based at least in part on a selected communication service to be provided and an available signal quality. A control unit receives data related to one or more selected communication services to be provided. The control unit also receives information about the environmental operating conditions in which the configurable receiver is operating, via one or more signal quality metrics. The control unit adjusts the operating mode of the configurable receiver by modifying the gain of a received signal, the channel bandwidth, or controlling the synthesizers or equalizers.

Abstract: A single chip superhetrodyne AM receiver is disclosed herein. To compensate for process variations in the implementation of the IC, bias currents setting the operating conditions for various amplifiers and other components in the system are adjusted based on frequency control signals in a PLL circuit in the local oscillator. Since the magnitude of the control signal reflects the process variations, the bias currents are adjusted based on the control signal to offset these variations in other portions of the receiver. To further improve the signal to noise ratio of the receiver, the IF filter is tuned within a range so as not to include any integer multiple or integer divisor of the timing reference frequency. Various techniques are described for enabling a complete superhetrodyne AM receiver to be implemented on a single chip which receives an antenna input signal and outputs a digital data signal.

Abstract: Noise floor searching is performed for a cellular base station to increase accuracy of receiver gain estimates. This allows adjustment of gain in a radio module to account for gain in front-end devices, and achieve a desired overall receiver target gain. The gain of the RF front-end devices is estimated based on the difference between measured Rx noise power at a receive port of the radio module and the noise floor of the radio module. In one embodiment, frequency sweeping across a receive band using a narrowband filter is done to search for minimum noise power. Interference detection may also be employed to increase awareness of any interfering signals that are presented at a configured channel. It is determined whether the interference is wideband or narrowband.

Abstract: The bandwidth of a first variable IF filter (5) for a neighbour channel suppression of a currently received channel, which first variable IF filter (5) is arranged in a first reception path of a broadcast receiver additionally comprising at least one second reception path is controlled by obtaining at least one first quality signal corresponding to a received broadcast signal on basis of a first filtering of the received and eventually pre-processed broadcast signal with said first variable IF filter (5) set to a predetermined bandwidth, obtaining at least one second quality signal corresponding to said received broadcast signal on basis of at least one second filtering of the received and eventually pre-processed broadcast signal with a second variable IF filter (13) arranged in said at least one second reception path with a bandwidth different to the first variable IF filter (5) bandwidth and/or with a different filter characteristic, and controlling the bandwidth of the first variable IF filter (5) on basi

Abstract: The invention provides a simple solution for a broadband transmitter/receiver for which the working bandwidth is split into at least two non-contiguous sub-bands. The invention uses a filtering means 50 which comprises at least two band-pass filters 51 and 52 provided with switching means 53 and 54. The use of two switched filters 51 and 52 makes it possible to use a single synthesizer 6 to scan two sub-bands of the working bandwidth. The frequency synthesizer 6 operates for one sub-band in supradyne mode and for the other sub-band in infradyne mode. In a variant, the invention uses a third filter and divides the bandwidth into three sub-bands.

Abstract: A signal processing circuit for a tuner has a detector band pass filter for extracting a carrier of an intermediate frequency signal, a frequency counter for counting, based on a clock signal, a frequency of a carrier of the intermediate frequency signal which passes through the detector band pass filter, and an intermediate frequency variation signal outputting section for outputting an intermediate frequency variation signal based on a difference between the counted frequency and a frequency of the clock signal. Based on the intermediate frequency variation signal, a frequency selection characteristic of an intermediate frequency band pass filter, a signal detector, an adjacent interference detector, or an S-meter-band pass filter are controlled.

Abstract: A tuner circuit includes a band selection filter coupled to receive an input RF signal and provide a band selected output signal where the band selection filter includes a bank of band pass filters. Each band pass filter includes an inductor and a variable capacitor forming an LC resonator where the inductor is an integrated planar spiral inductor. The tuner circuit further includes a frequency conversion circuit coupled to receive an input signal corresponding to the band selected output signal and provide a frequency converted output signal having a predetermined frequency. The integrated planar spiral inductor can be formed using a single metal spiral or multiple metal spirals. In a multi-spiral structure, a first metal spiral having an inward spiral pattern and a second metal spiral having an outward spiral pattern to form an inductor with large inductance, low series resistance and high Q values, even at low frequency.

Abstract: A system and method for direct current offset correction are disclosed. One embodiment of the system includes a direct current offset correction circuitry having an adjustable bandwidth and control logic configured to effect a bandwidth change of the direct current offset correction circuitry to speed up warm-up and settling time of the direct current offset correction circuitry.

Abstract: The invention relates to detecting a narrowband signals from received signals. According to the different aspects of the invention, a sample set is first formed from received signals, whereby elements of the sample set represent their absolute values, and a lower reference value and an upper reference value are determined. Then adjacent samples exceeding the lower reference value are grouped in the same cluster. The purpose of the clustering is to group signals possibly originating from the same source together. Then, if at least one of these clustered samples exceeds also the upper reference value, it is most probable that the cluster is caused by a narrowband signal. The order of the determination steps can be varied according to the different aspects of the invention.

Abstract: A method and apparatus for adjusting usage of digital signal processing (DSP) in a handheld terminal receives reception level data and reception quality data from a network, compares the received reception level data value and reception quality data value with pre-stored basis values, and then adjusts present usage of DSP based on the comparison result. Through this method and apparatus, usage of digital signal processing elements in the terminal is automatically optimized, thereby providing stable communication service to users.

Abstract: A method for power control in an ultra wideband impulse radio system includes: (a) transmitting an impulse radio signal from a first transceiver; (b) receiving the impulse radio signal at a second transceiver; (c) determining at least one performance measurement of the received impulse radio signal; and (d) controlling output power of at least one of the first transceiver and the second transceiver in accordance with the at least one performance measurement.

Abstract: RFID tags, tag circuits, and methods adapting the reception bandwidth. A tag has a decoder for decoding a first received wireless signal subject to a reception bandwidth setting. The tag also has a selector switch for transitioning to a different setting, such as by switching to using a different filter. A subsequently received second signal is decoded subject to the new reception bandwidth setting.

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: The invention relates to a method for tuning a filter (5). The filter has at least one variable time constant, by which the location of the pass band (pc) of said at least one filter can be changed. In the method, at least one reference signal is inputted in said filter (5), and the frequency of said at least one reference signal is changed, and/or said at least one time constant of the filter (5) is changed. The method also comprises the steps of measuring the strength of the output signal of the filter (5) and determining, on the basis of the measurement on the strength of the output signal of the filter (5), the location of the pass band of said filter (5).

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 for direct tuning of a radio receiver begins by providing a plurality of frequency-dependent control input signals to an input of the radio receiver.