Abstract: A composite beamforming technique is provided wherein a first communication device has a plurality of antennas and the second communication has a plurality of antennas. When the first communication device transmits to the second communication device, the transmit signal is multiplied by a transmit weight vector for transmission by each the plurality of antennas and the transmit signals are received by the plurality of antennas at the second communication device. The second communication device determines the best receive weight vector for the its antennas, and from that vector, derives a suitable transmit weight vector for transmission on the plurality of antennas back to the first communication device. Several techniques are provided to determine the optimum transmit weight vector and receive weight vector for communication between the first and second communication devices so that there is effectively joint or composite beamforming between the communication devices.

Abstract: Methods and apparatus for selecting a serving sector in a high rate data (HDR) communication system are disclosed. An exemplary HDR communication system defines a set of data rates, at which a sector of an Access Point may send data packets to an Access Terminal. The sector is selected by the Access Terminal to achieve the highest data throughput while maintaining a targeted packet error rate. The Access Terminal employs various methods to evaluate quality metrics of forward and reverse links from and to different sectors, and uses the quality metrics to select the sector to send data packets to the Access Terminal.

Abstract: A system, method, apparatus, means, and computer program code for improving accuracy of radio timing measurements. According to embodiments of the present invention, a terminal may obtain a measurement of each of a plurality of radio transmission sources at a distinct instance in time. In addition, a radio timing measurement for a common radio source is obtained for each of the distinct instants in time. The result will be a pair of radio timing measurements for each distinct instance in time containing smaller adjustment errors than radio timing measurements for all radio sources obtained for one common instant in time. The pairs of radio timing measurements can be used to more accurately support applications in which the geographic position of the terminal is obtained.

Abstract: Circuitry to transmit an analog data signal over a wireless communication link includes a receiver that receives a data signal, an automatic gain control circuit that keeps a peak amplitude of the data signal substantially constant and within a predetermined linear amplification range, and a transmitter, having the predetermined linear amplification range, that receives the data signal from the automatic gain control circuit and that outputs the data signal.

Abstract: A transmitting and receiving unit includes a receiving branch and a transmitting branch that are in each case constructed for conducting complex signals, with a control device that drives a switch by which either a phase-locked loop is switched through to frequency converters provided at the transmitting and receiving end, for providing a common carrier frequency, or in each case an independently operating PLL is provided for the transmitting and receiving branch. Such a configuration enables the transmitter, for example, to operate with direct conversion whereas the receiver can operate, for example, on the low IF principle. The invention is suitable for OFDM multi-carrier systems.

Abstract: The invention provides a composite high frequency component constituting a part of a microwave circuit having plural signal paths corresponding to their respective frequencies, comprising: a diplexer for coupling transmitting signals from the plural signal paths for transmission and distributing receiving signals into said plural signal paths for reception; plural high frequency switches for separating the plural signal paths into a transmission section and a reception section, respectively; plural filters introduced in the signal paths; said diplexer, said high frequency switch, and said filters being integrated into a ceramic multi-layer substrate formed by lamination of plural ceramic sheet layers. According to the above described composite high frequency component, the diplexer, the high frequency switches, and the filters which constitute the composite high frequency component are integrated into the ceramic multi-layer substrate formed by lamination of plural ceramic sheet layers.

Abstract: The invention relates to a method and a base station of a radio system implementing the method and to an antenna array of the base station which enable both antenna diversity and beam forming using the same antenna array. In the solution described the antenna array comprises, in addition to a linear part configured for beam forming, a non-linear part which is used for forming diversity. Furthermore, the non-linear part enlarges the aperture of the antenna array, thus improving the quality of beam forming.

Abstract: There is provided a radio transmitting apparatus capable of improving spectrum efficiency and a transmission rate while maintaining communication quality. The present apparatus adaptively selects space multiplex where different information (transmission signal A≠transmission signal B) is transmitted from a plurality of antennas with the same frequency, frequency multiplex where different information (transmission signal A≠transmission signal B) is transmitted from the plurality of antennas with different frequencies, space diversity where the same information is transmitted from the plurality of antennas with the same frequency, and frequency diversity where the same information (transmission signal A=transmission signal B) is transmitted from the plurality of antennas with different frequencies according to circumstances of a propagation path.

Abstract: An electronic radio system multifunction slice (100) for a electronic radio system (400). The slice (100) includes an antenna interface (102), several multi-band transceivers (106-112), a processor (104), and an avionics interface (114). The antenna interface (102) couples to the antenna preconditioners of the aircraft. The processor (104) is coupled to the multi-band transceivers (106-112) and antenna interface (102), and controls the transceivers (106-112) and antenna interface (102) to provide signal and data processing for at least two independent radio function threads. The processor (104) is also coupled to the avionics interface (114), which connects to the avionics network of the aircraft. Each multifunction slice 100 provides a programmable multifunction radio.

Abstract: A search and rescue beacon includes a main transmitter transmitting a Cospas-Sarsat signal at a main frequency and an auxiliary homing transmitter transmitting a homing signal at a homing frequency close to the main frequency. Advantageously both the Cospas-Sarsat signal and the homing signal are generated by a single synthesizer switching between a main Cospas-Sarsat burst transmission and a continuous homing frequency transmission of the homing signal. The Cospas-Sarsat signal is advantageously transmitted at a higher power than the homing signal. The single synthesizer may use a single amplifier chain. The single synthesizer and amplifier chain may use a single antenna.

Abstract: Voltage controlled oscillator (VCO) gain tracking is used for programming modulation gain settings to minimize modulation distortion in a low bandwidth phase locked loop of a mobile station (10). A synthesizer (20) generates a tuning voltage (Vt) for controlling a frequency of a voltage controlled oscillator (VCO) modulated radio frequency signal. A controller (22) outputs a modulation data signal and includes an analog to digital converter (72) for receiving the tuning voltage from the synthesizer (20) on a VCO feedback loop (70), a gain control lookup table (LUT) (76) for storing modulation gain setting calibration data for respective mobile station sub-bands, and a gain setting digital to analog converter (DAC) (78) for outputting a modulation gain control signal to the synthesizer (20). The modulation gain setting calibration data is calibrated using a one-time or continuous calibration methodology during, respectively, a background or normal mode of mobile station operation.

Abstract: A high-frequency device includes an antenna terminal, a signal line connected to the antenna terminal, a high-frequency signal processing circuit connected to the signal line, a capacitance element having one end connected to the signal line and other end grounded, and an inductor having one end connected to the signal line and other end grounded. The high-frequency device can protect the high-frequency signal processing circuit from a high voltage noise, such as a static electricity, having a frequency close to a signal pass band.

Abstract: An Automatic Gain Control system (AGC) in which an adder adds a Radio Frequency (RF) signal power of only the low-frequency component of a RF signal and an intermediate-frequency (IF) signal of an output from a variable-gain intermediate-frequency amplifier, which is higher than the frequency of the low-frequency component, and outputs the result to an A/D converter. This construction makes it possible to input power data for the RF stage to a demodulation LSI. The demodulation LSI separates the low-frequency component from the input signal, and by detecting the power of the extracted signal, is able to obtain the output data for the RF signal, and it separates the IF component from the input signal, and by detecting the power of the extracted signal, is able to obtain the output data for the IF signal.

Abstract: The invention provides systems, methods, and devices that compensate for temperature, frequency, and sampling effects in a broadband communication device's power measurements. One embodiment of a system includes a thermal device, and an automatic gain control circuit coupled to the thermal device. One method includes the acts of disabling a TOP operation, setting a RF input power, reading an AGC GAIN value, and setting the broadband communications device based on the read AGC value. Furthermore, a broadband communications device according to the invention may operate by disabling a TOP operation, setting a RF input power, reading an AGC GAIN value, and setting the broadband communications device based on the read AGC value.

Abstract: A phase lock loop receives a baseband signal which has an input frequency, and modulating the baseband signal to be a corresponding RF signal which has a predetermined transmission frequency for transmitting. The phase lock loop comprises a programmable divider, a modulator, a phase detector, a charging pump, a loop filter, a voltage-controlled oscillator and a frequency converter. The programmable divider divides the frequency of a local oscillating signal by a programmable divisor to generate a reference signal. The modulator receives the baseband signal, modulates the frequency of the reference signal according to the baseband signal, and generates a corresponding first comparison signal. The frequency converter receives the feedback RF signal and the local oscillating signal and outputs the second comparison signal according to the frequency difference. The divisor of the divider is programmable to avoid the spur frequency being generated because the local oscillating signal is interfered.

Abstract: An equalizing device with notch compensation for a direct conversion receiver is disclosed. The baseband signal of a direct conversion receiver comprises a notch in the frequency response after the required DC compensation is performed. A bandpass generates a notch compensation signal on from a decision signal and a interference compensation signal of a decision feedback loop. Therefore, the reliability of the decision signal is enhanced and allows an improved data rate in WLAN applications.

Abstract: An ultra-wideband transmitter and receiver, and a ultra-wideband wireless communication method, which perform ultra-wideband wireless communication by a low-speed digital circuit having a low power consumption and controlling the effect of a multi-pass. In ultra-wideband transmitter, delay time controller generates and inputs a periodic pulse to a first matched filter, outputs the periodic pulse to a second matched filter when data to be transmitted are at a first level of a binary logic level, and outputs the periodic pulse to a third matched filter when the data to be transmitted are at a second level of the binary logic level. The first matched filter receives the periodic pulse from the delay time controller and outputs a reference signal for data determination the second matched filter receives the periodic pulse from the delay time controller and outputs a first data signal earlier than the reference signal by a predetermined time.

Abstract: Techniques for improved low latency frequency switching are disclosed. In one embodiment, a controller receives a frequency switch command and generates a frequency switch signal at a time determined in accordance with a system timer. In another embodiment, gain calibration is initiated subsequent to the frequency switch signal delayed by the expected frequency synthesizer settling time. In yet another embodiment, DC cancellation control and gain control are iterated to perform gain calibration, with signaling to control the iterations without need for processor intervention. Various other embodiments are also presented. Aspects of the embodiments disclosed may yield the benefit of reducing latency during frequency switching, allowing for increased measurements at alternate frequencies, reduced time spent on alternate frequencies, and the capacity and throughput improvements that follow from minimization of disruption of an active communication session and improved neighbor selection.

Abstract: A frequency synthesizer usable in a wireless communication device is disclosed that may ensure a low phase noise and an improved performance. The frequency synthesizer has a phase locked loop comprising a controllable oscillator generating an output signal with an output frequency that can be adjusted within a predefined frequency range dependent on the value of a first control signal. A phase/frequency detector generates an error signal in response to a phase and/or frequency difference between an input signal generated by frequency dividing said output signal, and a reference signal. A loop filter generates the first control signal based on said error signal and outputs same to the controllable oscillator. A control unit generates a second control signal from the loop filter signal and provides the second control signal to the controllable oscillator, which is arranged for modifying the predefined frequency range based on the second control signal.

Abstract: An improved receiving phased array communication system supplies oscillating waveform signals with different phase delays to downconverting mixers in the processing channels of the receiving phased array communication system to compensate for phase difference in the received signal over the antenna elements therein. Similarly, an improved transmitting phased array communication system supplies oscillating waveform signals with different phase delays to the upconverting mixers in the processing channels of the transmitting phased array communication system to introduce phase difference in the transmit signal for transmission over the antenna elements therein. The oscillating waveform signals with different phase delays are preferably derived from a local oscillator that generates a local oscillating signal, and a delay line network having a plurality of fixed delay lines arranged in a serial manner to introduce increasing fixed phase delays in the local oscillating signal.

Abstract: An apparatus and method of for attaching an antenna to a mobile communication device. The apparatus can include radio frequency generation circuitry, a radio frequency feed point coupled to the radio frequency generation circuitry, a direct current voltage source coupled to the radio frequency feed point, and an antenna detection module coupled to the radio frequency feed point and the direct current voltage source. The antenna detection module is configured to detect a type of antenna coupled to the radio frequency feed point based on a detected direct current voltage. The antenna detection module can be coupled to the radio frequency feed point and a ground contact point. The apparatus can additionally include a parameter of operation adjustment module coupled to the antenna detection module. The adjustment circuitry can be configured to adjust a parameter of operation of the mobile communication device.

Abstract: A communications receiver includes a baseband signal recovery circuit which uses a low-IF architecture for data reception. The baseband signal recovery circuit uses a full-analog implementation for channel selection and filtering. Thus, the overhead placed on the design of analog-to-digital converter is greatly relaxed and most of hardware can be re-used for multi-mode applications with only a slight modification.

Abstract: A frequency agile sequential amplifier circuit that includes first and second RF amplifiers coupled by a SAW delay line, a double balanced mixer coupling the first RF amplifier to the SAW delay line, the output of the first RF amplifier providing a signal as a first input to the double balanced mixer and a variable pulse generator coupled to both said first and second RF amplifiers to cause them to sequentially and alternately conduct, and a divide/2 circuit coupling said variable pulse generator to said double balanced mixer as a second input at ½ the rate of said RF amplifiers to cause the sequential amplifier circuit to achieve frequency agility and to substantially maintain its sensitivity.

Abstract: The present invention relates to miniaturization of a local signal generation circuit to supply signals to a frequency converter in communication terminals such as a transmitter, a receiver, a transmitter-receiver, and the like that use one or more frequency bands. The local signal generation circuit comprises first and second oscillators capable of changing output frequencies and a multiplication means for multiplying input signals and generates local signals. The multiplication means selectively generates a signal of frequency corresponding to a sum or a difference between an output signal from the first oscillator and an output signal from the second oscillator.

Abstract: A communications network system and a corresponding method for starting an AoC service of a user are disclosed. The system comprises a control means for sending a protocol message comprising a MIME indication of an AoC application to a user equipment (UE). The user equipment receives the protocol message and activates the AoC application by using the MIME indication.

Abstract: A method for providing message notification in a wireless network includes receiving from a subscriber a message that is to be sent over the wireless network, receiving from the subscriber a requested notification type and a requested notification destination, processing the requested notification type and the requested notification destination, and sending the requested notification type to the requested notification destination.

Abstract: A text centre takes in telephonic text message calls. The text centre determines the target address(es) of the calls, and the identity of the target address(es) in each case is recorded in the text centre against a telephone call centre or call centres. The text messages are then sent to the call centre or call centres corresponding to the target address(es). For each call centre the text message calls received there are processed such that a future return call time is assigned to each of the text message calls. For each text message call the call centre concerned automatically forwards a return text message to the telephone concerned, the return text message contains details of when a return telephonic voice call will be made from the call centre to the holder of the telephone. The return voice calls are then made.

Abstract: A method and system for providing transmission of a selected media program to a wireless handset includes a source provider, such as a wireless network or a wireless handset, for receiving a transmission from at least one media program provider. At least one wireless handset transmits a request selecting one of the media programs. In response thereto, the source provider simultaneously transmits the selected media program to each of the wireless handsets.

Abstract: A System and method for ascertaining the state of a mobile communication apparatus. The state is ascertained by collecting data which can be allocated to individual components (C1, C2, C3) and/or procedures (P1, P2, P3) embedded within the mobile communication apparatus on the basis of status quo information deriving from the respective components (C1, C2, C3) and/or procedures (P1, P2, P3) and by radio transmitting the collected data from the mobile communication apparatus via the radio network to which the mobile communication apparatus is affiliated to a certain service center.

Abstract: A gateway for mobile communications comprises a cache for storing network data recently downloaded from a network, a foreign agent, and a packet filter that directs requests for the network data from a mobile node to the cache. The packet filter directs the requested network data from the cache to the mobile node by way of the foreign agent, without forwarding the requested network data to a home agent of the mobile node.

Abstract: A system and apparatus for redirecting wireless network traffic. Embodiments include determining when a roaming mobile station initiates a registration attempt with a non-preferred network and causing the roaming mobile station to initiate a registration attempt with a preferred network. Embodiments further include a traffic redirection network entity including a traffic redirection node, a traffic redirection application, and a traffic redirection probe.

Abstract: A radio communication system has means for enabling the control channels associated with a data channel transmitting packet data with a low duty cycle to be switched to a dormant state or interrupted entirely. This reduces the excessive overhead that such control channels represent on a data channel only using a small proportion of the available channel capacity.

Abstract: A scheme that enables seamless roaming between the WLAN and the cellular carrier network by enabling a user that originates a call in the WLAN and happens to go outside the range of the WLAN to automatically switch over to the cellular carrier network without losing connection with the other party. This solution assumes that the mobile device has the capability to operate in at least two modes that include the WLAN mode and one of the cellular carrier modes, such as the GSM, IS-95 CDMA, IS-136 TDMA, and iDEN.

Abstract: The invention relates to a data transfer method in a radio system utilizing a multiple antenna method, the data transfer method comprising generating, at a receiver, at least part of a change in a variable which contains transmit filter information on a transmitter as compared with a previous value of the variable, transmitting at least part of the change in the variable containing transmit filter information on the transmitter from the receiver to the transmitter and updating, at the transmitter, the transmit filter information on the transmitter on the basis of the received change in the variable containing transmit filter information. The invention further relates to a radio system implementing the method. In the solution, the amount of data used for updating transmit filter information and to be transmitted to a transmitter can be optimised, which enables unnecessary loading of radio capacity to be avoided.

Abstract: Techniques to efficiently attempt acquisition of a packet data system (e.g., an IS-856 system). If a terminal has acquired one or more channels in a voice/data system (e.g., an IS-2000 system), then it can attempt acquisition on channels in the packet data system that are co-located with the acquired channels in the voice/data system. Multiple acquisition modes may be used, and on-going acquisition attempts on the co-located channels may be performed using one acquisition mode at a time in order to reduce power consumption. Acquisition attempts may be performed in a “ping-pong” manner to improve the likelihood of acquisition. For a ping-pong search, an acquisition attempt is made on the most recently acquired channel prior to an acquisition attempt on each of the remaining channels. Received signal strength estimates may also be obtained for selected channels and may be used to determine whether or not to attempt acquisition on these channels.

Abstract: A method of monitoring frequency availability for a telecommunications network includes: establishing details of frequency spectrum usage in a database, said details to include one or more of time of use, frequency and geographic area of use; and providing query means for the database, to allow the contents of the database to be queried.

Abstract: The present invention discloses a node selection procedure. A load is obtained, having a priority level. The first step selects a node from a first subset of available nodes. If the node is capable of accepting the load, i.e. if the congestion level is low enough to allow a load of the present priority level, the node is selected as a destination node. If the congestion level of the node is too high to allow the node to accept the load, the second step is performed. The second step creates a second subset of nodes, all capable of accepting the load. One of the nodes is then selected as destination node. This second selected node is guaranteed to be able to accept the load. The load is then directed to the selected destination node. If the second subset is empty, the load has to be discarded.

Abstract: A method is provided of communicating data over an interface from a base station of a network for mobile telecommunications to a base station controller. The base station controller is operative to control the base station. The method comprises storing user data and diagnostic data for transmission, selecting user data for transmission in preference to diagnostic data, and selecting diagnostic data traffic for transmission when no user traffic data is stored for transmission.

Abstract: Apparatus, and an associated method, for facilitating frequency offset estimation between communication stations operable in a communication system. A likelihood polynomial is calculated and provided to a filter. The filter forms a filtered representation of the likelihood polynomial, and the filtered representations are down-sampled by a decimator. A sampled, filtered representation of the likelihood polynomial is thereby obtained. The filtered, sampled representation is applied to a root calculator that calculates the roots of the polynomial, thereafter, to be used to compensate for the frequency offset.

Abstract: An apparatus and method and provided for tracking the location and direction of an individual utilizing a direct radio frequency link between a mobile target and a mobile monitor. The apparatus and method utilize a mobile target device which may be affixed to an individual to be tracked utilizing a secure attachment mechanism. A mobile monitor device in bi-directional communication with the mobile target device is additionally provided. This radio frequency communication is encrypted in nature, thereby preventing unauthorized tracking of an individual by an non-intended third party. The mobile monitor device broadcasts the relative distance and direction between the mobile monitor device and mobile target device to a mobile monitor operator. A Bluetooth® enabled microprocessor may be utilized in transmitting and receiving this encrypted signal.

Abstract: The invention provides location information indicating the geographical location of a mobile station via a core net-work node serving the mobile station The method includes the steps of initiating a communication between the mobile station and the network by calculating the geographical location, supplying corresponding location information indicating the geographical location to the core network node, and subsequently routing the communication between the mobile station and the network.

Abstract: Disclosed is a method and apparatus for locating a wireless device especially useful for locating a cellular telephone making a call from an unknown location. The call may be a request for emergency assistance, or for location-based commercial services, for example. Various embodiments may optionally include a mobile location component, a cellular telephone enabled to chirp-on-demand, and/or an interferometer link. A mobile location component may include a directional antenna. The directional antenna may be mounted on an antenna boom on top of an emergency vehicle, for example. The mobile location component may alternately or additionally comprise a hand-held unit. System elements may cooperate to generate a situation awareness map or other display. The mobile location component may be moved in the general direction of a first location calculation associated with a first circular error of probability.

Abstract: Disclosed is a cooperative element location system especially useful for locating a cellular telephone making a call from an unknown location. The call may be a request for emergency assistance, or for location-based commercial services, for example. Various embodiments may optionally include a mobile location component, a cellular telephone enabled to chirp-on-demand, and/or an interferometer link. A mobile location component may include a directional antenna. The directional antenna may be mounted on an antenna boom on top of an emergency vehicle, for example. The mobile location component may alternately or additionally comprise a hand-held unit. System elements may cooperate to generate a situation awareness map or other display. The mobile location component may be moved in the general direction of a first location calculation associated with a first circular error of probability.

Abstract: A system, consisting of an ultrasonic transmitter and a receiver, is described for controlling certain electronic sound-generating and radio-frequency-generating devices. In restricted areas where the audible sound generated by these electronic devices is objectionable, one or more ultrasonic transmitters are placed to blanket the area, each emitting an ultrasonic signal periodically. In electronic devices having ultrasonic receivers, the receipt of this signal prevents the electronic device from generating or reproducing objectionable audible sound for a short period of time after receipt of this ultrasonic signal, which is slightly longer than the period in which the ultrasonic signal is sent.

Abstract: A telecommunication network (TN) comprises a radio access network (2) defining cells in which user equipments (7) are localized and a core network (1) linked to the radio access network and adapted to establish a multimedia broadcast multicast context for the user equipments (7) located in the cells.

Abstract: A control message transmitting/receiving method in an MBMS-supporting mobile communication system. In the present invention, an RNC periodically transmits control messages related to MBMS RB setup to UEs. Thus, although a UE initially fails to receive an intended MBMS service, it can set up an MBMS RB by receiving a related retransmitted control message. Also, the RNC periodically provides information about ongoing MBMS services on a cell basis so that a UE can decide whether its requested MBMS service is in progress and request information required to set up an MBMS RB for the MBMS service to the RNC by individual signaling.

Abstract: An apparatus transmits an analog data signal over a wireless communication link. The apparatus includes a base unit having a wired connection to a telephone line. The base unit transmits data to and from the telephone line via the wired connection. The apparatus also includes a remote unit having a wired connection to a modem. The remote unit transmits data to and from the modem via the wired connection. The remote unit and the base unit communicate with each other over the wireless communication link. The base unit includes a radio frequency transmitter to transmit the analog data signal to the remote unit and an automatic gain control circuit that keeps a peak amplitude of the analog data signal substantially constant and within a linear amplification range of the radio frequency transmitter.

Abstract: The present invention is directed to a mobile telephone relaying system or unit for relaying communication signals between a mobile telephone capable of wireless communication with a wireless mobile telephone communication system and a wired telephone in a wired local telephone network providing communication between the wired telephone and a wired telephone communication system for allowing communication via the wired telephone using the wireless telephone network. According to an exemplary aspect of the present invention, a mobile telephone relaying unit may be coupled to the wired home telephone network for relaying communication signals between the mobile telephone and the wired local telephone network for communication with the wired telephone. The wired telephone network may employ communication signals having a first format, and the mobile telephone communication signals may have a second format.

Abstract: For the purpose of being capable of performing direct inter-handset communications while maintaining inter-handset communications via a base unit, smoothly making a transition from inter-handset communications via a base unit to direct inter-handset communications, and switching to inter-handset communications via a base unit without releasing the communications even in case direct inter-handset communications cannot be established, a local handset includes a direct inter-handset communications controller and a direct inter-handset communications transition controller for making control to establish direct inter-handset communications while maintaining communications with a base unit as well as transmitting control channels for direct inter-handset communications in vacant slots in the receiving time zones for communications with the base unit, while a distant handset includes a direct inter-handset communications controller and a direct inter-handset communications transition controller for scanning control

Abstract: Channel estimation and spatial processing for a TDD MIMO system. Calibration may be performed to account for differences in the responses of transmit/receive chains at the access point and user terminal. During normal operation, a MIMO pilot is transmitted on a first link and used to derive an estimate of the first link channel response, which is decomposed to obtain a diagonal matrix of singular values and a first unitary matrix containing both left eigenvectors of the first link and right eigenvectors of a second link. A steered reference is transmitted on the second link using the eigenvectors in the first unitary matrix, and is processed to obtain the diagonal matrix and a second unitary matrix containing both left eigenvectors of the second link and right eigenvectors of the first link. Each unitary matrix may be used to perform spatial processing for data transmission/reception via both links.