Abstract: The present invention provides a search window delay tracking procedure for use in a multipath search processor of a CDMA radio receiver. A channel impulse response is estimated for a received signal containing plural paths, each path having a corresponding path delay. A search window defines a delay profile that contains the plural paths of the received signal. A mean or average delay is calculated for the estimated channel impulse response (CIR), and an error is determined between the mean CIR delay and a desired or target delay position of the Cir. search window. An adjustment is made to reduce that error to align the targeted position of the search window and the mean CIR delay. A Doppler frequency is estimated for each path. The adjustment is made taking into account a Doppler effect caused by relative movement between the transmitter and receiver.

Abstract: A radio receiver is provided with a beam-width-variable antenna that receives a radio signal and is capable of changing the beam-width; an interference canceler for removing interference waves from the received radio signal and outputting an interference-wave-removed signal; a measuring device for measuring reception quality of the received signal based on the interference-wave-removed signal; and a beam-width controller for controlling the beam-width of the beam-width-variable antenna based on the reception quality from the measuring device.

Abstract: A system and method for applying an algorithm to distance measurements between nodes in an ad-hoc communications network. The algorithm is located at an individual node of the ad-hoc network and processes collected data via a multi-path filter to ensure that range measurement data is correct, and if so, include such measurement data in a historical data matrix in which old measurement data is eliminated. During periods where received signals are unable to provide correct distance measurements due to reflections affecting the path between nodes or media absorption or radio energy, distance estimates may be obtained from this accurate historical data.

Abstract: In a radio communication apparatus, delay profiles of a desired wave and delay waves thereof are estimated by plural delay profile estimation sections for each of received signals from directional antennas constituting an array antenna. Received signals from the antennas selected by a reception antenna selector on the basis of the delay profile are subjected to a temporal/spatial equalization processing by an adaptive signal processing section and a path diversity combining section, thereby obtaining a reception output. An arrival angle range of the desired wave is estimated by a DOA estimation section from the delay profile estimated by the delay profile estimation section. Based on the arrival angle range, the antenna for transmission is selected by a transmission antenna selection section, and transmission signals are sent out.

Abstract: Method for data transmission in a wireless local area network refers to wireless local area networks (WLAN) consisting of a multitude of transceivers capable of establishing communication with one another (i.e. operating in a peer-to-peer mode). Implies the determination of the quality of communication between all transceivers and storage of communication quality data by each of the transceivers. Based on stored data on communication quality, a transceiver operating in the transmission mode transmits information to an addressee by a transmission route that provides for the quality of communication, which is equal to or better than a specified threshold value of communication quality. Stored data are updated periodically. The method improves the quality and reliability of communication for WLAN users (including mobile users) thus increasing the data transmission rate.

Abstract: Techniques to estimate the frequency response of a wireless channel in an OFDM system. In one method, an initial estimate of the frequency response of the wireless channel is obtained for a first group of subbands based on a pilot transmission received via the subbands in the first group. An estimate of the impulse response of the wireless channel is then derived based on the initial frequency response estimate. An enhanced estimate of the frequency response of the wireless channel is then derived for a second group of subbands based on the impulse response estimate. The first and second groups may each include all or only a subset of the usable subbands. Subband multiplexing may be used to allow simultaneous pilot transmissions by multiple terminals on their associated groups of subbands.

Abstract: A method and apparatus for calibrating a Base Station and Mobile Station for use in systems that use round trip delay and systems that do not use round trip delay.

Abstract: A testing chamber is configured to evaluate the accuracy of a wireless communication device under test in a production environment. The configuration of the testing chamber may resemble an enclosed structure having a wall that includes multiple layers. An array of antennas, which serves as a layer of the wall, is strategically positioned within the testing chamber to receive and transmit signals emitted to/from the wireless communication device. Located within the testing chamber is either a stationary or moveable holder to support the wireless communication device. Furthermore, during testing, the forward link and the reverse communication links are monitored by selectively or alternatively adjusting and shifting the phase/amplitude of the antenna of the wireless communication device to mitigate the effects of multi-path fading.

Abstract: A radio apparatus includes an antenna (104), and a transmission circuit (102) and a receiving circuit (105) sharing the antenna. The apparatus connects an output of the transmission circuit to an input of the receiving circuit in calibration for calculating the quantity of phase rotation and/or the quantity of amplitude fluctuation of a signal passing through the transmission and receiving circuits. Then, it connects a reference signal to the input of the receiving circuit for calculating the quantity of phase rotation and/or the quantity of amplitude fluctuation of a signal passing through the receiving circuit. Based on the subtraction of the information, the quantity of phase rotation and/or the quantity of amplitude fluctuation of a signal passing through the transmission circuit is calculated. It calculates a correction value for correcting difference in quantity of phase rotation and/or quantity of amplitude fluctuation between the transmission and receiving circuits on the basis of the information.

Abstract: Techniques to correct for phase and amplitude mismatches in a radio device in order to maintain channel symmetry when communicating with another device using MIMO radio communication techniques. Correction for the amplitude and phase mismatches among the plurality of transmitters and plurality of receivers of a device may be made at baseband using digital logic (such as in the modem) in the receiver path, the transmitter path or both paths of that device. In a device, amplitude and phase offsets are determined among the plurality of radio transmitter and radio receiver paths by measuring phase and amplitude responses when supplying a signal to a transmitter in a first antenna path of the device and coupling the radio signal from a first antenna to a second antenna path of that device where the signal is downconverted by a receiver associated with the second antenna path, and similarly coupling a signal from the second antenna path to the first antenna path.

Abstract: A method and apparatus for uniquely identifying signal sources in a multisource signal. True levels of signal components transmitted by each of the co-channel base stations in the area under test in a wireless network are measured and associated with the appropriate (originating) base station in presence of co-channel and adjacent-channel interference without interrupting service. The present invention is based on an “area-measurement” approach and relies on relative time-of-arrival (RTOA) measurements of the signal components impervious to the existence of the phase drift between the scanner and base stations.

Abstract: A wireless communication terminal that ensures communication using a frequency band suitable for line-of-sight communication even if an obstruction is present in a wireless communication path or a status of a radio wave propagation path dynamically changes. An initial detecting section detects whether it is possible to communicate with another terminal of a master station mode. If communication is possible, a slave-mode setting section sets up a slave station mode, registers the other terminal in a master terminal storage section and transmits to the other terminal a communication indicating that a local terminal is subordinate to the master terminal. If communication is not possible, a master-mode setting section sets up a master station mode when a transmission is received indicating that the other terminal is subordinate to the local terminal. A slave terminal registration section registers the other terminal in a slave terminal storage section.

Abstract: Method and device for the detection of one or more mobiles within a communications network, the method comprising at least one step for the “acquisition” of at least one RACH type signal exchanged between a mobile and a base station of the network and a step to measure the angle of arrival of the signal, the measurement step being synchronized with a parameter of the exchanged signal. Application to the GSM network.

Abstract: The invention relates to a device for aiding the analysis of signals by using symbols-based digital modulation. The device includes a signal memory for storing a complex digital signal, representative in amplitude and phase of a captured signal, over a chosen duration, as well as a processor for searching for the properties relating to the carrier frequency of the complex signal and to its modulation. According to the invention, the processor includes a projector for calculating the components of the complex signal in a function basis, the function basis being parameterized according to an estimated tempo of the modulation, as well as a calculator, operating on these components so as to determine an estimate relating to a property of the complex signal, from among its elementary pulse shape, the string of symbols of the complex signal and its carrier.

Abstract: A wireless communication network processes composite loop-back signals received at one or more network antennas from a plurality of mobile stations, each transmitting an individual, mobile-specific loop-back signal. Using its knowledge of the prior network-transmitted signal(s) from which the mobile stations derive their individual loop-back signals, and its knowledge of the mobile-specific loop-back signal modifications made by each of the mobile stations, the network derives mobile-specific downlink channel information based on processing the composite loop-back signals. That is, use of the mobile-specific loop-back signals enables the network to determine downlink channel estimates as between each participating network antenna and each participating mobile station to be used for transmit signal interference and/or power pre-compensation, for example.

Abstract: Systems and methods according to the present invention are described for adjusting the number of taps in an adaptive equalizer over time as the rate of change of a communications channel varies. The number of taps or “equalizer length” is adjusted based on an estimate of the Doppler frequency between the devices communicating over a channel. The Doppler frequency is reflective of the rate of change of the communications channel. Greater Doppler frequencies indicate a more quickly varying channel, and vice versa. It is therefore desirable to change the equalizer length (by adding or dropping taps) based on a measurement of the Doppler frequency. Equalizer length is increased as the Doppler frequency decreases. Conversely, equalizer length is decreased as the Doppler frequency increases. This enables the equalizer to achieve a better compromise between the competing goals of adaptation speed (less taps) and ISI reduction (more taps).

Abstract: A method (100) is provided for transmitting a traffic signal with an adaptive antenna array of a base transceiver such that a subscriber unit utilizes a non-dedicated pilot transmitted from a reference antenna element for demodulation of the traffic signal. The method (100) comprises determining a channel impulse response from a plurality of antenna elements in operative communication with the base transceiver to a receive antenna of the subscriber unit (102).

Abstract: A method detects relaying of a contactless data communication by a radio amplifier for intercepting and manipulating the communication to achieve an unauthorized authentication. The method involves transmitting an electromagnetic field successively from at least two spatially separated antennas of a transmitting unit, receiving the transmitted fields in a receiving unit, determining field strength vectors of the received fields allocated to each antenna, and comparing actual values of the vectors with prescribed nominal values stored in a nominal value field that maps the true field strength distribution in multi-dimensional space around the transmitting unit. The actual field strength magnitude and the reception angle between the transmitting antennas can be determined from the vectors and compared with stored nominal values in this manner. When the determined actual values match prescribed nominal values of the nominal value field, the occurrence of a relaying of the signal can be reliably excluded.

Abstract: Apparatus for Doppler correction in a wireless communications system, including a first frequency synthesizer for generating a carrier signal oscillating at a rate responsive to a first input, a counter coupled to the first input for generating a Doppler compensation signal, the counter having a clock input, and a second frequency synthesizer coupled to the clock input for generating a clock signal oscillating at a rate responsive to a rate input. The rate input is adjusted over time according to a predetermined sequence so that the Doppler compensation signal compensates for the Doppler effect experienced by, for example, ground-to-satellite communications in a satellite communications system.

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: A wireless communication system computes the pilot phase measurement RMSE directly by determining the path width as measured by the searcher component of the modem, the path drift over time, and the measurement resolution. The path width may be based on a measurement error that is half the path width or the larger of the distances from the local maxima to the earliest or latest side. Optionally, the distance from the peak to the 3 dB-down point can be used if the search resolution permits such measurement. The path drift is multiplied with the uncertainty in the measurement time stamp to get an error. This error is added to the measurement error due to path width. The measurement resolution is also added to the error.

Abstract: A method of anticipatorily estimating the radio coverage by a base station of a cell of a cellular wireless telephone network includes devising a numerical map having a direct-access data matrix of local and independent specifications for the positions and types of salients of a plurality of predetermined meshes of a mesh topology corresponding to the map. In an operational phase, a simulated sampling beam associated with the radioelectric propagation conditions is transmitted in the cell along an initial path segment from an initial position and along a determined direction and under determined conditions of propagation. The position of the instantaneous site is compared with the mesh topology to identify an incidence mesh at a salient. Post-incidence propagation conditions are computed on the basis of local and independent data for salients of the incidence mesh.

Abstract: A personal radiation-alerting device for use with a cellular telephone is provided. The radiation alerting device may comprise a radio frequency (RF) sampling unit adapted to measure the amplitude of the electromagnetic field generated by the cellular telephone over time, a computing unit adapted to compute the amplitude over time and to compare it with a predefined reference level and an alerting unit adapted to output an alert whenever the electromagnetic field exceeds the predefined reference level.

Abstract: A bulk delay estimating circuit matches time intervals representing a signal with time intervals representing an echo of the signal to identify the echo and estimate bulk delay. Bulk delay is estimated by computing (1, 2, . . . n) intervals representing the signal, computing (1, 2, . . . n) intervals representing an echo of the signal, computing absolute differences between corresponding intervals to produce n absolute differences, summing the n absolute differences, and providing an output indicating whether or not the sum is less than a predetermined amount. The intervals are determined by defining a plurality of numbered frames, comparing the energy of a signal during each frame with at least one threshold, storing the numbers of the frames in which the threshold is exceeded, and defining an interval as the period from one frame in which the threshold is exceeded to the next frame in which the threshold is exceeded.

Abstract: According to the invention, a connection between a base transceiver station and a subscriber station is allocated a transmission rate for signal transmission from the base transceiver station to the subscriber station on the basis of a connection-specific level of path damping.

Abstract: An object of the present invention is to provide a method for detecting a shield in predicting the radio wave propagation characteristics by a technique of the geometrical optics capable of detecting a content which a ray strikes, at high rate, when the ray is radiated within the observation space. In the case where the rays and the contents are given, the projected objects given by the line or plane are set up, and if an image of the content projected onto the projected object and an image of the ray projected onto the projected object do not intersect, the content is excluded from the shield detection object. A plurality of projected objects i (i=1 to M) are prepared, the selection of shield detection object is performed for each projected object i in order for i=1 to M, and the content of the shield detection object is concluded in sequence.

Abstract: An antenna device for transmitting and receiving electromagnetic waves, wherein the antenna device includes a transmitter section and a receiver section. The receiver section includes a receiving antenna structure selectively switchable between a plurality of configuration states. The antenna structure may be switched by a switching device, which is controlled by a control device. The selective switching is effected based upon a first measure representing a reflection coefficient measured at the transmitter section. A method for transmitting and receiving electromagnetic waves includes receiving a measure representing a reflection coefficient and controlling a switching device to selectively switch an antenna structure between a plurality of antenna configuration states in response to the measure representing the reflection coefficient.

Abstract: Disclosed are systems and methods which select multiple communication beams for simultaneous use such that potential scatters (e.g. reflectors) are not illuminated by simultaneous transmissions. Preferred embodiments of the present invention provide for maximizing aggregate throughput by continuously selecting the best subscriber station combination to be serviced simultaneously, such as based upon their spatial status and Quality of Service (QOS) metrics. Additionally or alternatively, embodiments of the present invention may facilitate demodulation reference using a system common pilot, training sequence, or other system signal.

Abstract: Bit error rate estimates are used for measuring link quality in a radio telecommunications system. Unbiased, raw bit error estimates are produced from existing pilot symbols. The bit error rate estimates may be generated without incurring extra signaling overhead. More particularly, an estimation of link quality is obtained by receiving control signals in a radio receiver, where each control signal may include one or more pilot symbols deriving a channel estimate for each control signal, modifying each channel estimate as a function of the corresponding control signal's contribution to the channel estimate, and deriving a link quality measure based on said modified channel estimates.

Abstract: To shorten a required estimation time while keeping an estimation precision in an object environment given for estimating propagation characteristics with a ray launching method. In the case where a ray is propagated within a given observation area, and collides with a barrier residing on its path, a space in the vicinity of the ray is divided into a plurality of partial spaces until a predetermined condition is satisfied. The space in the vicinity of the ray that is considered to cause a degradation in the estimation precision is divided in reflection until there is less influence of degradation, whereby each of the subdivided partial spaces can be handled individually, so that the estimation precision of radio wave propagation characteristics can be made better than a conventional method.

Abstract: The composition of an object within a wireless communication channel is determined by analyzing a symmetry characteristic of a polarization pattern of a received signal. The signal is transmitted through the communication channel using a known polarization. A receiver receives the signal and determines a symmetry characteristic of the polarization pattern of the received signal. The symmetry characteristic is matched to a stored symmetry characteristic to determine the composition of the object. Based on the composition of the object, the susceptibility of the wireless communication channel to wind-induced fading can be determined.

Abstract: A wireless communication system includes at each cell at least one network part of the system communicating with subscriber terminals in its area. Within the system, a method for transmitting reception information on a receiving end to a transmitter includes measuring the quality of a signal received from a terminal, such as the bit error ratio (BER) of the signal, and transmitting the measured quality information to the terminal to be indicated to the user of the terminal, or transmitting an announcement selected on the basis of the quality information to the terminal via the network part to be indicated to the user.

Abstract: A locator using Navstar constellation signals for determining geographical location of a mobile receiver. The locator is integrated with a mobile unit of a cellular network, which derives its reference frequency from a local oscillator (26). A frequency measuring module (28) counts the number of digital numbers derived from the local oscillator passing between two consecutive time-tagged indicators of the cellular network. The estimated frequency is calculated by dividing the number of digital numbers by the nominal time interval (T0) between the indicators.

Abstract: There is disclosed a signal monitoring apparatus for use in a wireless network base station containing a modular main unit for processing baseband signals and a modular radio unit separate from the main unit for transmitting and receiving radio frequency (RF) signals. The signal monitoring apparatus is disposed in the radio unit and monitors an RF output signal transmitted by a transceiver in the radio unit. The signal monitoring apparatus comprises an RF mixer that mixes the RF output signal and receiver local oscillator (LO) signal used by the receiver portion of the transceiver to demodulate received RF signals. The RF mixer generates an intermediate frequency (IF) signal capable of being transmitted through a communication line at relatively low signal loss to a signal measuring device located in the main unit or elsewhere.

Abstract: A device and a method for the rejection of interference in a payload signal are described. The method includes evaluating the interference phase and evaluating the instantaneous amplitude of the interference by the least error squares method, forming a ratio r=(B2/(A2+B2)) where A is the real part of the amplitude of the interference and B is the complex part of the amplitude of the interference. If r is below the threshold value r0, the signal is corrected by replacing the central sample of the signal by a weighted sum moderated by the central sample and neighboring samples.

Abstract: A method for forming signals at a transceiver having at least two transmit and receive chain, the method comprising the steps of: (a) determining the phase difference and relative amplitude of signals from a set comprising a plurality of mobile stations as received through the receive chains, (b) receiving from each of at least one of the mobile stations messages indicative of the strength or quality of signals as received by the respective mobile station from the transceiver and on the basis of those messages determining a phase offset and amplitude distortion, internal to the transceiver, resulting from the differences in the instrumental properties of the receiver and transmitter chains in the transceiver; and (c) transmitting signals from each of the transmitter chains by applying to each transmitter chain amplitude weights and signal delays, selected on the basis of the determined phase offset and amplitude distortion, and received relative amplitudes and phase differences.

Abstract: Proposed is a method for reducing interference in a frequency hopping wireless communications system. In one embodiment of the present invention, a base station and a terminal station each using an orthogonal frequency division multiplexing (OFDM) technique to simultaneously measure an interference level for each system frequency and to enable high speed frequency hop pattern changes which can follow changes in desired and interfering signal levels due to changes in co-channel interference or shadow fading. The terminal station interference level measurement values are then transmitted to the base station. Next, the base station identifies each frequency hop pattern currently in use by each terminal station communicating with that base station.

Abstract: A process for simultaneously measuring the propagation characteristics of a plurality of radio-frequency channels. According to the invention, from several base stations are transmitted signals whose spectra are interleaved. At the receive end, each of these spectra may be reproduced and the impulse response of each channel may be calculated. Application to radio-communications with mobiles.

Abstract: In a RAKE receiver delays associated with multipath signals are determined by subtracting power values associated with sidelobes of a peak value for each of the multipath signals. The determination can be performed in two stages, in the first stage the determination of the delays is made without accounting for a phase difference between adjacent multipath signals, while in the second stage the determinations are made accounting for the phase difference.

Abstract: Estimation of a signal to interference ratio in a cellular communications system is described wherein an estimate for interference is the weighted sum of individual interference estimates along each of a plurality of multi-paths, weighted according to estimates of the signal power, likewise along each of a plurality of multi-paths.

Abstract: A method and apparatus tests CDMA signal propagation and coverage. A pn scan is first made of the pilot channel to be measured. The signal to total power ratio, Ec/Io is calculated. A frequency scan is made of the reception frequency close in time to the pn scan. The frequency scan results are used to identify and quantify any interference adjacent and coincident with the CDMA channel of interest. The power of the interfering transmissions are weighted, interfering signals with frequencies close or within the CDMA channel of interest are given heavier weights. Removing weighted value of the interfering signals modifies and reduces the value of Io. An adjusted Ec/Io is calculated to reflect the modified Io value, thus resulting in an approximation of the Ec/Io value at the transmission site. The sources of interference can be reported to the CDMA carrier for remedial attention.

Abstract: A method of simultaneously determining a DC offset and a channel impulse response from a received signal in a mobile communication system. The received signal comprising a set of training sequence bits that have been modulated prior to transmission. The modulated signals experience a certain phase shift and are rotated by a certain angle. The received signal may also comprise a DC offset component that needs to be removed. By manipulation of the received signal samples with the knowledge of the original training sequence and method of modulation used, it is possible to simultaneously estimate the communication channel's impulse response and the DC offset by finding the Least Squares solution to a linear equation, such that the energy of the noise term introduced into the communication channel may be kept to a minimum. An improved technique utilising a priori information is also described.

Abstract: A method and system for distance measurement in a low or zero intermediate frequency (IF) half-duplex communications loop provides a mechanism for measuring the distance between two transceivers without synchronizing the local oscillators of the two transceivers. Transceiver distance may be measured in systems that use direct conversion (zero IF) or intermediate frequencies that are so low that phase noise significantly reduces the accuracy of the distance measurement. The communications loop is closed by demodulating, re-modulating and re-transmitting a received signal to provide a re-transmitted signal that has the same carrier and modulation frequency as the received signal. A phase-hold circuit provides an analog system for half-duplex operation that retains the frequency and phase information of the received signal for retransmission in a subsequent time slot.

Abstract: A method of remotely estimating the functionality of a preamplifier mounted adjacent an antenna at the top of a mast or tower and coupled to a base station via a transmission medium, such as a coaxial cable, includes taking noise and/or signal power measurements at the base station via the coaxial cable for the amplifier when both powered and unpowered. The ratio of the respective noise and/or signal powers, after the receiver noise figure at the base station and the cable loss (estimated or measured) including any connection device loss are accounted for, provides an estimate of the functionality of the amplifier.

Abstract: Determination of a received signal strength indication in a direct conversion receiver begins by determining, at a given time, a 1st value to be the larger of the in-phase component of the received signal and the quadrature component of the received signal. The direct conversion receiver then determines a 2nd value at the given time to be the smaller of the in-phase component of the received signal and the quadrature component of the received signal. As such, at a given time, the 1st and 2nd values correspond to the greater and lesser of the in-phase component and quadrature component, respectively. Having obtained these values, the direct conversion receiver then determines the received signal strength indication based on the 1st value, the 2nd value and an offset value. The offset value provides a scaling of the RSSI value based on the range of the RSSI values.

Abstract: Briefly, a portable communication device that is able to block transmission of a link quality indicator is provided. The transmission of the link quality indicator may be blocked if the quality level of a channel is below or at a threshold. The threshold may be generated according to a target quality level.

Abstract: A wireless communication system (10). The system comprises a user station (12). The user station comprises despreading circuitry (22) for receiving and despreading a plurality of slots received from at least a first transmit antenna (A121) and a second transmit antenna (A122) at a transmitting station (14). Each of the plurality of slots comprises a first channel (DPCH) comprising a first set of pilot symbols and a second channel (PCCPCH) comprising a second set of pilot symbols.

Abstract: The selection of the primary control signal bus to use for a given radio head is based on propagation delay to the relevant radio head. A plurality of radio heads are cascaded in a chain with buffered error correction therebetween. At least first and second control interfaces connect to the chain and supply control information thereto via respective control signal busses, which may be virtual busses. The propagation delay from a first control interface to a first radio head over a first bus is determined. Likewise, the propagation delay from a second control interface to the first radio head over a second bus is determined. Thereafter, the radio head determines which control signal bus to select as its primary control signal bus based on the respective propagation delays between the first radio head and the first and second control interfaces.

Abstract: An apparatus and method are disclosed for acquiring by a mobile terminal a pseudo-random noise (PN) sequence of a pilot signal received from a base station by means of a searcher, designating a phase of the acquired PN sequence as a reference phase to track the phase of the acquired PN sequence, and measuring an energy difference between an early path and a late path for the reference phase in a mobile communication system. In the apparatus and method, a first energy measurer measures a first energy value from a PN sequence with the reference phase, and a second energy measurer alternately measures energy values of the early path and the late path for the reference phase and outputs a second energy value.

Abstract: Methods of designing, installing and operating communications systems including multiple input multiple output (MIMO) antenna arrays are disclosed. The methods account for the diffusive nature, the polarization nature, and the multi-path nature of the environment in which the antenna arrays operate. According to the various methods, the antennas can be designed, installed and operated so as to provide improved information capacity based on the diffusive, polarization and multi-path nature of the environment in which they operate.