Abstract: Circuits, systems, and methods are disclosed for controlling multiple antenna receive paths in a wireless communication device. In some embodiments, the circuit may include a pair of receiving antennas, a first receive path including a VCO coupled to receive a PLL signal and a first mixer coupled to receive a first signal from the VCO and a signal from one of the antennas, and a second receive path integrated separately from the first receive path including a second mixer coupled to receive a second signal from the VCO and a signal from the other antenna. By utilizing the output of the VCO to tune the first and second mixers in the first and second receive paths to the same phase and frequency, control of the multiple antenna receive paths may be optimized.

Abstract: A communication system with an antenna array having a respective antenna for each of a multitude of communication modules and a control system which seiectiyely reassigns communication over a first of said multitude of communication modules to a second communication module of said multitude of communication modules in response to identification of a predicted interference within a predetermined interference matrix.

Abstract: An improved antenna arrangement and synchronization system for use when multiple radio base stations, using a deterministic over the air MAC layer, are located within overlapping coverage areas is disclosed and more specifically the method described here discloses an improved antenna and coordination arrangement for use at the base station which will eliminate over the air collisions while doubling the effective data rate of each base station. The result being large area networks which all share exactly the same radio spectrum without mutual interference and with little effort required to expand a single base station system into a grid of cooperative base stations forming a coverage area of ubiquitous coverage and multiplied data capacity.

Abstract: The present invention eliminates the need for an anti-aliasing filter in a receiver that employs an analog-to-digital converter. By maintaining a predetermined relationship between a local oscillator frequency and the sampling frequency of the analog-to-digital converter, aliasing that would normally occur in the desired pass band is avoided. More specifically, the frequency of the periodic signal provided to the mixer is an integer multiple of half the sampling rate of the analog-to-digital converter. In a preferred, non-limiting example embodiment, the sampling rate of the analog-to-digital converter FADC and the frequency of the local oscillator FLO are related by the following: FLO=n*FADC/2, where n is any positive integer.

Abstract: The invention is directed to a receiver arrangement, for example, in a mobile radio, which allows the use of slowly locking phase locked loops for a point-to-point connection between two transceivers, even in the case of a heterodyne receiver structure. The need to change channels between a transmission slot and a reception slot is avoided by virtue of a changeover device being provided for the purpose of interchanging the in-phase and quadrature components at the input side on a down-conversion frequency mixer. This advantageously allows either the upper sideband or the lower sideband of a useful signal to be down-converted without the need to change channel.

Abstract: Described is a communication system including mobile communication devices. In the described system, the mobile devices many be wrist-worn watches such as are in common use today, except that the watches are specially configured to receive data in a “broadcast” mode and transmit and/or receive data in a “localcast” mode. The localcast mode includes the ability to transmit and receive data in a peer-to-peer fashion, allowing mobile devices to communicate directly with each other. The ability to combine two of these communication modes in a tiny, integrated and hence cheap and low-power package provides many advantages over existing personal communication device solution.

Abstract: Embodiments of the present invention provide a system, method, and apparatus of receiving signals of a plurality of communication services. The apparatus may include, for example, a plurality of multimode receivers to receive signals of a plurality of wireless communication services, wherein the number of the plurality of communication services is equal to or greater than the number of the plurality of multimode receivers; and a controller to control a receive mode of the plurality of receivers. Other embodiments are described and claimed.

Abstract: Rejection of local oscillator harmonic response is provided in a mixing circuit with a pair of harmonic gating switches serially connected to the outputs of a balanced differential switching mixer and controlled by a gate clock signal having twice the frequency of a local oscillator signal controlling the switching mixer. An aperture or duty cycle of the gate clock signal determines which harmonic is rejected or suppressed, which is preferably a third and/or fifth harmonic since response of the balanced differential switching mixer to even harmonics is negligible. The resulting simple, efficient circuit is readily integrated directly into a phase-alternating mixer structure for a chopper-direct-conversion radio.

Abstract: In a broadcast receiving system, a first antenna receives a broadcast signal of a first frequency band and a second antenna receives a signal of a second frequency band different from the first frequency band. A frequency conversion unit converts the signal of the second frequency band into a second signal of the first frequency band. A selection unit selects one of the broadcast signal output from the first antenna and the second signal output from the frequency conversion unit. A demodulation unit demodulates the one of the broadcast signal and the second signal selected by the selection unit.

Abstract: An apparatus determines an optimal antenna and frequency combination by selecting the optimal antenna from among a plurality, N, of antennas associated with a receiver and also selects the optimal frequency from among a plurality, M, of alternative receiving frequencies transmitted from a transmitter. This is achieved by determining all N×M possible antenna/frequency combinations, by determining the received signal quality at each combination, by comparing the N×M received signal qualities, and by selecting the one antenna/frequency combination having the optimal received signal quality.

Abstract: Methods and systems consistent with this invention receive a plurality of transmitted signals in a receiver having a plurality of receive elements, wherein each transmitted signal has a different spatial location. Such methods and systems receive the plurality of transmitted signals at the plurality of receive elements to form a plurality of receive element signals, form a combined signal derived from the plurality of receive element signals, and detect each of the plurality of transmitted signals from the combined signal by its different spatial location. To achieve this, methods and systems consistent with this invention generate a plurality of arbitrary phase modulation signals, and phase modulate each of the plurality of receive element signals with a different one of the phase modulation signals to form a plurality of phase modulated signals.

Abstract: An antenna steering algorithm for a smart antenna uses signal quality metrics and link quality metrics for selecting a preferred antenna beam. The link quality metrics supplement the signal quality metrics for improving the antenna steering decision. The link quality metrics are based on information available from existing counters operating in the media access control (MAC) layer. Separate estimates of the frame error rates in the receive links and in the transmit links are obtained. One estimate is the downlink quality metric (DLQM) and another estimate is the uplink quality metric (ULQM). Alternative link quality metrics are based on throughput and data rates of the exchanged data.

Abstract: A switch circuit for switching the connection of the receiving or transmitting circuits of two communication systems to an antenna circuit, which comprises first and second switch means having two switching elements, the first switch means comprising a first inductance element between a port connected to the antenna circuit and a port connected to the second switch means; the second switch means comprising a second inductance element between a port connected to the first switch means and a port connected to a receiving circuit of a first communication system, and a transmission line constituting the first inductance element having a lower characteristic impedance than that of a transmission line constituting the second inductance element.

Abstract: The method and apparatus herein identifies tunable duplexer in a communication system. The tunable duplexer includes a tunable receiver filter, a tunable transmitter filter, a variable receiver phase shifter, and variable transmitter phase shifter. Each filter and phase shifter is optimized based on characteristics of impedance within the duplexer. The duplexer may be adjusted to changing environments or desired changes in the frequency of operation, reducing circuitry architecture and providing greater flexibility in communication function. The method commences by tuning tunable filters within the duplexer and then optimizing phase shifters within the duplexer for adjusting impedance matching with antenna and isolating the receiver from the transmitter during duplexing operations. Optimizations and calibration may be performed during manufacture, upon initialization of the system, or during operation of the communication device.

Abstract: A radio communication apparatus using an array antenna has a plurality of reception branches for conveying reception signals received at the antenna element of the array antenna, and a calibration branch for selecting one of the plurality of reception branches and conveying the reception signal. Channel estimations are made respectively on the reception-branch signals and a calibration-branch signal. RAKE composition is made on the channel estimation values, a result of which is used to detect amplitude and phase deviations on the reception branch thereby carrying out a correction.

Abstract: An RF transceiver module for wireless communication devices includes a multi-layered substrate, an RF transceiver IC mounted on the multi-layered substrate for receiving and transmitting voice or data signals, at least one band selection filter mounted on the multi-layered substrate for filtering received RF signals, an antenna switch integrated in the multi-layered substrate which can be switched to transmit RF signals generated by the power amplifiers to the external antenna or to receive RF signals from an external antenna to the RF transceiver IC through the band selection filter, a plurality of passive devices embedded in the multi-layered substrate, and wiring embedded in the multi-layered substrate for electrically connecting the passive devices, the RF transceiver IC, and the band selection filter.

Abstract: A received wireless signal contains a plurality of path components, each having a phase indeterminate data stream derived from an original data stream. The receiver splits the received signal into N signal copies for N raking channels, which correlate each of the N signal copies with N locally generated signals, respectively, to generate N correlated signals. Each of the N correlated signals carries an estimated phase indeterminate data stream. The raking channels then synchronize each of the correlated signals to a system clock in phase and frequency to generate N synchronized signals. The N raking channels then align the N synchronized signals to generate N aligned signals, each of which carries an aligned path data stream that is normalized in time with respect to the other aligned signals. Finally the receiver combines the aligned signals to produce an estimated original data stream.

Abstract: A communication signal receiver and associated method are disclosed. A plurality of communication signals are received at an atenna array and time multiplexed into a single multiplexed signal. Each of the communication signals comprises an unknown mixture of a plurality of source signals from a plurality of communication signal sources. A signal separation network is configured to separate the K source signals from the multiplexed signal.

Abstract: A method and apparatus for switching signals through a switch matrix are disclosed. The apparatus comprises an input module and an output module. The input module has a plurality of inputs typically equal to a number of cells in a reuse pattern, and the inputs receiving at least one uplink beam. The input module also has a plurality of outputs, the plurality of outputs is typically equal to the number of subbands in the uplink beam. The output module is coupled to the input module and selectively couples the outputs from the input module to an output of the output module. The method comprises the steps of grouping the uplink signals into a plurality of groups, the number of groups typically equal to a number of cells in the cell-based transmission matrix, where each group comprises a signal from each frequency used in the frequency reuse pattern. Each group of uplink signals is then separated into subband signals, which are then grouped together into groups of similar subband signals.

Abstract: Methods and apparatus implementing spatial processing in a remote unit. In general, in one aspect, the present invention provides a remote unit, that includes a plurality of antennas and a spatial processing unit coupled to the plurality of antennas. The remote unit also includes a performance determination unit to determine a performance of the remote unit and a feedback adjustment unit to adjust feedback transmitted from the remote unit to a device, wherein the adjusted feedback accounts for performance associated with the spatial processing unit.

Abstract: The present invention relates to a wireless communication device, such as a transponder, that has a plurality of antennas for multi-frequency usage. The wireless communication device comprises a control system, communication electronics, memory, and the aforementioned antennas. A wireless communication device having a pole antenna may be used with one or more loop conductor antennas to achieve the desired operating frequencies. A wireless communication device having a dipole antenna may be coupled across a loop conductor antenna to provide different loop conductor configurations depending on the frequency.

Abstract: A closed-loop transmitting antenna diversity method, and a base station and mobile station apparatus therefore in a next generation mobile telecommunications system, the closed-loop transmitting antenna diversity method having a plurality of antennas in a mobile telecommunications system, including the steps of (a) measuring the changed amount per unit time of the phase difference between antennas for each of the plurality of antennas which are used in a base station; (b) transmitting the result of measuring as feedback information for adjusting transmitting antenna diversity; (c) receiving and interpreting feedback information in the base station; (d) calculating the weighted value of array antennas for each antenna, using the interpreted feedback information; and (e) multiplying data which is to be transmitted from the base station to a mobile station by the array antenna weighted value, and outputting the result through a corresponding antenna.

Abstract: A mobile wireless communication device (10) having a direct conversion receiver (20) reduces spurious mixer response by predicting blockers on the received RF signal. The chopping frequency of the mixer is changed (305) dynamically in response to the prediction of blockers on the input signal to avoid the mixing the blocker with chopper spurs, thereby improving the response of the receiver. In some embodiments, the mixer is disabled momentarily (402) to verify that poor signal quality results from mixing chopper spurs with blockers. In hopping mode applications, the chopper frequency is changed only on channels having a low confidence factor (512).

Abstract: Embodiments of the present invention provide a method, apparatus and system for path searching, including computing a set of slope-normalized operator values corresponding to a set of respective signal samples.

Abstract: Methods and systems consistent with this invention receive a plurality of transmitted signals in a receiver having a plurality of receive elements, wherein each transmitted signal has a different spatial location. Such methods and systems receive the plurality of transmitted signals at the plurality of receive elements to form a plurality of receive element signals, form a combined signal derived from the plurality of receive element signals, and detect each of the plurality of transmitted signals from the combined signal by its different spatial location. To achieve this, methods and systems consistent with this invention generate a plurality of arbitrary phase modulation signals, and phase modulate each of the plurality of receive element signals with a different one of the phase modulation signals to form a plurality of phase modulated signals.

Abstract: An impulse waveform generating apparatus comprises an oscillator for generating a reference signal having a center frequency in a frequency band of an impulse to generate, a timing matching circuit for shifting a phase of the reference signal by 90 degrees, a frequency demuultiplier for dividing a frequency of the phase shift signal and obtaining a timing signal having a frequency component having a frequency width of an impulse to generate, a memory storing a waveform shape table, a waveform forming section for forming a waveform in synchronism with the timing signal, according to information of a shape table having a predetermined waveform, a low-pass filter for obtaining an envelope signal from an output signal of the waveform forming section, and a waveform generating section for changing an amplitude of the reference signal according to a value of the envelope signal.

Abstract: Integrated RF components in the radio frequency (RF) front end of a communication device. The RF front end includes an antenna function for converting between radiated and electronic signals, includes a filter function for limiting signals within operating frequency bands, an amplifier function for boosting signal power and a mixer function for shifting frequencies between RF and lower frequencies. The receive antenna function is separate from the transmit antenna function where a common integrated filter/antenna (filtenna) is employed for both the receive path and the transmit path.

Abstract: A radio communication apparatus subjects each signal which is received via a multi-path and demodulated, to a Hadamard transform at each of fingers, by use of an M-ary quadrature coding scheme, obtains correlation values of codes, combines correlation values output from fingers which obtain valid correlation values, and demodulates a received signal based on a maximum correlation value of combined correlation values. The radio communication apparatus includes an operation unit which obtains a difference between a maximum value and a second largest value of the correlation values of a corresponding one of the fingers, and a lock controller which enables and locks the correlation values output from the corresponding one of the fingers when the difference obtained by the operation unit is greater than or equal to a predetermined value.

Abstract: A radiotelephone system for motor vehicles, having a group antenna system with a plurality of antenna elements, and a mobile radiotelephone with a high-frequency input for receiving radio signals. The group antenna system contains controllable phase and/or amplitude adjusting elements, which are set so that a directed reception with a main receiving direction is available. The controllable phase and/or amplitude adjusting elements are controlled by a processor for tracking the main receiving direction azimuthally in the direction of a fixed station with the help of a tracking signal. Controllable switching-elements for reversing antenna signals for diversity reception are integrated in the signal paths of the group antenna system so that the azimuthal main direction of reception is tracked with a defined tracking by setting a combination of the switching positions of the controllable switching elements.

Abstract: A receiver provides received analog signals to a plurality of channel branches, and on at least one of the channel branches, the frequency of the received analog signals is adjusted independent of the relative positions of the corresponding analog signals in the radio frequency (RF) spectrum. The analog signals on the channel branches are then combined, and the combined analog signals are converted into the digital domain. For example, the receiver comprises at least one antenna(s) which receives radio frequency (RF) analog signals. A channel branch arranger receives the analog RF signals from the antenna(s) and provides the RF analog signals to a plurality of channel branches.

Abstract: A method of effectuating frequency switching by using two self-oscillating frequency reducers having a common input includes the use of a three-way coupler to connect two field effect transistors (or two bipolar junction field effect transistors) and two dielectric resonator oscillators between a low-noise amplifier and an intermediate frequency (IF) amplifier, so as to effectuate switching between different frequency ranges. Thus, a simplified switch circuit for switching frequencies is possible to enable reduced manufacturing cost and reduced volume of device.

Abstract: The invention relates to a method of implementing transceiver operation at a base station. In the method, at least two transmitter units (300, 302) in different sectors transmit signals at different frequencies to the same multifrequency amplifier (306), and the signals amplified by the multifrequency amplifier (306) are transmitted to a filter structure (500), which filters signals to be transmitted at different frequencies. In the method sector-specific antennas (418, 420) transmit and receive the signals at different frequencies and the filter structure (500) filters the at least two signals received at different frequencies. The filtered signals are transmitted via the filter unit (400) to the receiver amplifier (404), whereupon the signals received from the different sectors are transmitted to sector-specific receiver amplifiers (406, 408).

Abstract: A universal remote control radio frequency transmitter for use with garage door operators, gate operators and other barrier movement operators is programmable through the use of external switches. The same switches are used after programming for causing the transmitter to transmit an RF signal at about the selected frequency and with a code corresponding to the programmed code. A plurality of RF frequencies are generated by a single RF circuit and a single loop antenna. The selected frequency is determined by digital controller logic and PIN diode shorting in and out selected reactive elements in the RF circuit.

Abstract: A radio transceiver circuit which includes an antenna, a transmitter, a receiver, an antenna switching circuit for selectively connecting the transmitter and the receiver to the antenna, and a power source for driving the transmitter and the receiver. The antenna switching circuit includes two semiconductor elements. The current (|BRX, |BTX) provided by the power source to the receiver and to the transmitter is directed through the respective semiconductor elements which are each set to its conductive electrical state by the respective current (|BRX, |BTX) and thereby selectively coupling the radio signal between the receiver and the transmitter to the antenna.

Abstract: A method and apparatus for selecting an optimal set of antennas from a plurality of antennas for use by a transmitter and/or receiver having a plurality of RF chains to transmit and/or receive a wireless signal on a wireless link. According to the invention information concerning transmission of wireless signals on the wireless link is determined and an optimal set of antennas from the plurality of antennas is selected based on the information. Thereafter, the RF chains are connected to the optimal set of antennas to permit transmission and/or reception of the wireless signal from the RF chains on the wireless link via the optimal set of antennas. The RF chains correspond in number to the number of antennas in the optimal set of antennas, and the number of antennas included in the plurality of antennas is greater than the number of RF chains.

Abstract: A space diversity antenna system provided with dither circuitry in the signal path to one of the antennas to switch a circuit element in and out of the signal path at a high rate. The circuit element can be an amplitude attenuator or a phase changer. This switching results in the substantial elimination of nulling between the two antennas.

Abstract: An analog processor for use with digital satellites is disclosed. The analog processor is connected between the receiving circuitry of the satellite and a pool of digital on-board processors, and segments the bandwidth of uplink RF beams into sub-bands that can be processed more readily with standard, low-risk, low-power digital processors. Using the present invention, the risk of employing a particular digital processor technology can be managed and optimized. The present invention also provides for the dynamic allocation and reallocation of the available on-board digital processing bandwidth based on the anticipated traffic pattern and changes in the traffic pattern. In addition, the present invention facilitates the use of standard and non-standard redundancy schemes at minimal hardware expense.

Abstract: An integrated circuit including a structure of inductances on a semiconductor substrate, intended for operating at frequencies greater than several hundreds of MHz, including a first inductance formed by a conductive track and having first and second terminals respectively connected to each of the two ends of the conductive track, including a second inductance formed by the conductive track between the second terminal and any intermediary point of the conductive track connected to a third terminal, said second and third terminals forming the two terminals of the second inductance, and means for setting the third terminal to high impedance when the first inductance is used.

Abstract: When demodulating data of each frame of a phase-modulated signal received by a selected one of antennas, a phase error detector detects a phase error as a deviation from an ideal phase, and an accumulator accumulates phase errors in the frames. If an accumulated value of the phase errors is greater than a predetermined value in a predetermined slot position in a frame, antenna switching is controlled for a next frame. In the antenna switching control process, the demodulated phase of a first antenna selected in a present frame is held in a phase holder. If the accumulated value of the phase errors becomes greater than the predetermined value, the first antenna is switched temporarily to a second antenna, and the demodulated phase of the second antenna is held in the phase holder. Based on reception statuses of the first and second antennas, either better one of the antennas is selected, one of the demodulated phases held in the phase holder is selected and provided to a demodulator.

Abstract: An adaptive transceiver architecture which reallocates communications resources in real time based on the amount of bandwidth being used in communications channels in the system. The transceiver receives communications signals from a plurality of communications beam spots. Each communications beam spot has a predefined bandwidth divided into non-overlapping subbands. The transceiver further comprises a plurality of front end signal conditioners for receiving communications signals from an equal plurality of communications beam spots. A predetermined number of the conditioned signals are then combined by an interconnect. The interconnect receives composite signals from the front end signal conditioners, and it combines at least first and second communications signals from first and second respective composite signals to form an output processing signal.

Abstract: A multi-channel digital transceiver (400) receives uplink radio frequency signals and converts these signals to digital intermediate frequency signals. Digital signal processing, including a digital converter module (426), is employed to select digital intermediate frequency signals received at a plurality of antennas (412) and to convert these signals to baseband signals. The baseband signals are processed to recover a communication channel therefrom. Downlink baseband signals are also processed and digital signal processing within the digital converter module (426) up converters and modulates the downlink baseband signals to digital intermediate frequency signals. The digital intermediate frequency signals are converted to analog radio frequency signals, amplified and radiated from transmit antennas (420).

Abstract: A receiving circuit includes a first antenna 1, a second antenna 2, units 10 and 11 for generating a sum signal or a difference signal from signals of two paths received by the respective antennas, a unit 12 for giving delay to either an output of the sum signal generating unit or an output of the difference signal generating unit, a unit 13 for summationally combining an output of the delay unit and the signal of the not-delayed path, a desired-wave pass filter unit 14 for receiving an output of the summationally combining unit, a dividing unit 15 for receiving an output of the desired-wave pass filter unit, an orthogonal detection unit 16-19 for receiving an output of the dividing unit, and a filter unit 20 and 21 for receiving an output of the orthogonal detection unit to extract a base band signal therefrom, wherein the receiving path including the summationally combining unit and the following are made into one path to thereby attain miniaturization and low power consumption.

Abstract: An apparatus for performance improvement of a digital wireless receiver comprises a processing circuit for processing a plurality of received signals and providing a processed signal where the received signals are multiplied by weights and combined; and a weight generation circuit for generating the weights; wherein the received signals are sampled at a multiple of a symbol rate, different weights for each set of samples at a symbol rate are generated and the weights are selected to optimize performance.

Abstract: The method and arrangement is for controlling a radio receiver. The arrangement has a central processor (DECT-C), a device (RSSI-C) for measuring the field strength of received signals, a threshold value generator (TH-C) and two antennas (A1, A2). The central processor (DECT-C) carries out method steps configured in such a way that different procedures (P1, P2) are realized to activate one of a plurality of antennas (A1, A2) of the radio receiver as a function of measured field strength values (RSSI1) of received signals and as a function of overshooting or undershooting of a threshold value (TH0).

Abstract: An analog processor for use with digital satellites. The analog processor is connected between the receiving circuitry of the satellite and a pool of digital on-board processors, and segments the bandwidth of uplink RF beams into sub-bands that can be processed more readily with standard, low-risk, low-power digital processors. Using the present invention, the risk of employing a particular digital processor technology can be managed and optimized. The present invention also provides for the dynamic allocation and reallocation of the available on-board digital processing bandwidth based on the anticipated traffic pattern and changes in the traffic pattern. In addition, the present invention facilitates the use of standard and non-standard redundancy schemes at minimal hardware expense.

Abstract: A subscriber antenna for use in a super high frequency multipoint fixed-access wireless system is provided which has several individually selectable directional antenna facets. The antenna is deployed in a cellular environment. The performances of the signals received by the antenna facets are prioritized, and the best performing facet is selected as a default facet. The antenna is particularly suited for use in a cellular system employing basestations sectorized by polarization to provide basestation diversity.

Abstract: An interferometric receiver for electromagnetic signals comprises at least two reception channels. Each channel consists of an antenna (A1), followed by a single sideband mixer (M12) and a mixer (M14).As a local signal, the mixer (M14) receives a signal similar to the received signals, taken, for example, from an auxiliary antenna (AR) followed by a limiting amplifier (ALR). The first mixer (M12) receives a frequency from a generator (GFI), which frequency is equal to the value of the intermediate frequency used in the stages (FI1) of this type following the mixer (M14). A phase processing can then be carried out and different countermeasures taken, the simplest of which is a visualization (VI).

Abstract: A method and apparatus of reducing interference in a broadband radio frequency link is disclosed. Different signals are received by two antenna elements, in a first case the signals comprise differently polarized signals at the same or an offset frequency; in a second case the signals comprise a wanted signal and an interference signal, wherein the interfering signal is treated as an independent channel. The method comprises the steps of receiving radio frequency signals on two independent paths, selecting a portion of the radio frequency signal in each receive path or the desired signal path after demodulation where a predetermined frequency or band of frequencies is known to be absent; measuring the signal power; determining weights in a feedback path; and applying the feedback control signals to an algorithm which determines the weight(s) applied to the wanted signal such that the signal power in the summed signal(s) due to the interfering signal is reduced or cancelled.

Abstract: A multi-channel digital transceiver (400) receives uplink radio frequency signals and converts these signals to digital intermediate frequency signals. Digital signal processing, including a digital converter module (426), is employed to select digital intermediate frequency signals received at a plurality of antennas (412) and to convert these signals to baseband signals. The baseband signals are processed to recover a communication channel therefrom. Downlink baseband signals are also processed and digital signal processing within the digital converter module (426) up converters and modulates the downlink baseband signals to digital intermediate frequency signals. The digital intermediate frequency signals are converted to analog radio frequency signals, amplified and radiated from transmit antennas (420).

Abstract: A transmitter/receiver apparatus employed with advantage in a radio communication system for radio transmission and reception of frequency division multiplexed or time-division multiplexed signals of the frequency division duplex system on switching between plural antennas includes a plurality of antennas for radio transmission/reception of the reception and transmission signals, a switch for switching between the antennas, a plurality of antenna duplexers connected to the antennas via the switch and having respective different frequency bands, a transmission unit connected to the antenna duplexers, a reception unit connected to the antenna duplexers and a control unit for controlling the switch, transmission unit and the reception unit. The control unit controls the switch so that an optional one of the antennas will be connected to the antenna duplexers of the frequency band corresponding to the frequency used in radio communication solely by the switching.