Abstract: Systems and methods are provided for transmitting OFDM signals through a communication channel exhibiting frequency selective fading, such as an aeronautical 2-ray channel, using a signal modulation scheme at the transmitter that is selected based on a measurement of signal to distortion ratio (SDR) at the receiver. The SDR measurement at the receiver is used to generate an estimated best modulation scheme based on the real-time detection and measurement of SDR at the receiver, and provide feedback to the transmitter through a feedback channel of the newly selected modulation scheme. In certain configurations, the selected modulation scheme is one of multiple possible quadrature amplitude modulation (QAM) schemes, which enables adaptation of the transmitted OFDM signal to optimize throughput based on distortion of individual tones of the OFDM signal received at the receiver.

Abstract: Mechanisms for determining an electrical phase relation between antenna elements in an antenna array. A method is performed by a radio transceiver device. The method comprises obtaining measurements of the radio signal as received in two receive beams covering a given angular sector. The two receive beams have different complex beam patterns. The method further comprises estimating the angle of arrival of the radio signal for at least one polarization port of each of the two receive beams using the measurements in the two receive beams. The method also comprises determining, from the angle of arrival estimated for each polarization port, an electrical phase relation between antenna elements in the antenna array that corresponds to the estimated angle of arrival.

Abstract: Single antenna direction finding is performed by physically moving a device to different device positions. As the device is physically moved, signal processing hardware within the device is used to make a plurality of signal response measurements of a wireless signal detected by a single antenna of the device. The wireless signal emanates from an object. The plurality of signal response measurements are made by sampling signal response at a plurality of sample times. An inertial measurement system makes a plurality of inertial measurements at the plurality of sample times. The plurality of signal response measurements and the plurality of inertial measurements are used to produce a virtual response array vector. The virtual response array vector is used to calculate a direction of arrival from the object to the device.

Abstract: High precision radar to track aerial targets installed on the ground, in a container or in a vehicle, to determine the target parameters, such as azimuth angle (?a), elevation angle (?e), range, speed and flying direction and transmits them to a weapon system which comprises an array of two collinear antennas (19, 21) with narrow beam in elevation, installed on a platform (12) and rotating around a vertical axis at a rotational speed of, at least, 50 rpm, in which the direction of the said array varies between 0° and 90° by means of a positioning motor in elevation (18), and the precise target elevation angle (?e) is determined by interferometry. The precise target azimuth angle (9a) is determined through correlation between a signal detected by the said antennas (19, 21) with a +1/?1 step function, complemented by the search for the zero transition provided by the determination of the return pulse maximum.

Abstract: A method comprising receiving audio information by way of a plurality of microphones comprised by an apparatus, determining at least one spatial audio property of the audio information in relation to the apparatus, determining an operational directive based, at least in part, on the spatial audio property, and performing one or more operations in conformance with the operational directive is disclosed.

Abstract: An electronic device which includes a plurality of microphones and an audio data processing module is provided. The plurality of microphones is operatively coupled to the electronic device, and the audio data processing module is capable of being implemented with at least one processor. The audio data processing module recognizes a specified command, based on first audio data collected using a portion of the plurality of microphones and executes a function or an application corresponding to second audio data collected using all the plurality of microphones, when the specified command is recognized.

Abstract: A measuring apparatus for measuring the trajectory of a target object includes a receiving device having a primary mirror and a secondary mirror; a first detector for detecting first electromagnetic radiation having a first wavelength and a second detector for detecting second electromagnetic radiation having a second wavelength. The primary mirror is designed to reflect the first electromagnetic radiation and the second electromagnetic radiation and to direct the radiation onto a focal region. The secondary mirror is arranged between the primary mirror and the focal region and is designed to reflect only the second electromagnetic radiation in the direction of the second detector. The first detector is arranged behind the secondary mirror in the focal region of the primary mirror.

Abstract: A neural network is provided for recognition and enhancement of multi-channel sound signals received by multiple microphones, which need not be aligned in a linear array in a given environment. Directions and distances of sound sources may also be detected by the neural network without the need for a beamformer connected to the microphones. The neural network may be trained by knowledge gained from free-field array impulse responses obtained in an anechoic chamber, array impulse responses that model simulated environments of different reverberation times, and array impulse responses obtained in actual environments.

Abstract: A spinal orthosis has an elongate and substantially rigid spinal frame having upper, middle and lower portions, and a lumbar assembly connected to the lower portion of the spinal frame. A strap assembly secures to an upper portion of the spinal frame and is adjustably secured to the lumbar assembly. An elastic strap has a first end secured to the spinal frame and a second end adjustably securing to the lumbar assembly.

Abstract: Systems, methods, circuits and computer-readable mediums are disclosed for sign detection in multi-dimensional signal measurements. In some implementations, orthogonally oriented antennas are configured to generate signals in response to a magnetic field, where the signals correspond to components of magnetic field vectors in space. A circuit is coupled to the antennas and configured to: determine polarities of the signals based on phase measurements between the signals; reduce a possible number of magnetic field vector interpretations based on the determined polarities of the signals; reduce a possible number of angles or angle differences between the magnetic field vectors based on the reduced possible number of magnetic field vector interpretations; compare the reduced possible number of angles or angle differences to predetermined angle or angle differences; and detect a relay attack based on results of the comparing.

Abstract: Multipoint wireless communications are coordinated in cells with radiation that is emanated from antennas in an inward direction. In an example embodiment, an apparatus includes a first antenna, a second antenna, a third antenna and a controller. The first antenna emanates radiation from a first location in an inwardly direction for a cell. The second antenna emanates radiation from a second location in an inwardly direction for the cell. The third antenna emanates radiation from a third location in an inwardly direction for the cell. The controller coordinates the emanation of the radiation via the first, second, and third antennas so as to reduce intra-cell interference for remote terminals located within the cell. The coordination may be effected in accordance with one or more coordinated multi-point (transmission/reception) (CoMP) techniques. Different numbers of sub-cells and antennas per cell and different CoMP cell organizations may be implemented.

Abstract: An evaluation device provides a transceiver system with performance information. The transceiver system models channels between a transmitter and a receiver thereof using Nakagami distribution with a fading parameter. The evaluation device includes a setting module, a computing module and an output module. The computing module is operable, based upon the fading parameter, an average SNR of the channels, a number of transmit antennas and a number of receive antennas, to estimate an average output SNR, a bit error rate and an outage probability related to signals received by the receiver. The output module is operable to provide the transceiver system with the average SNR and the estimated information as the performance information.

Abstract: A sensing system includes integrated sensor locating capability. Sensors can transmit spread spectrum encoded data pulses which are received at mobile nodes. Based on time of arrival information and known locations of the mobile nodes, locations of the sensors can be determined.

Abstract: A communication apparatus that can suppress an increase in circuit size and reduce influence of interference, includes reception array antenna elements, a reception digital beam forming (DBF) network that generates a reception beam signal for forming M reception beams using a reception signal, and reception filter banks (FBs) that generate frequency split reception beam signals obtained by frequency-splitting the reception beam signal. The communication apparatus includes an interference-source detecting unit that stores, for each reception beam, an interference candidate beam area estimated based on an initial reception beam characteristic, calculates, based on the frequency split reception beam signals, a reception spectrum, and calculates, based on the reception spectrum and a reception spectrum of a reception beam to the interference candidate beam area, an interference source area.

Abstract: A wireless communication method and apparatus are provided for selecting quality-reporting sub-carrier bands based on sub-carrier band quantity information received from a base station. The method includes generally four steps. First, from a base station, information indicating quantity of sub-carrier bands is acquired. Second, channel quality of each of a plurality of sub-carrier bands within a communication band is measured from a received signal. Third, sub-carrier bands are selected from the plurality of sub-carrier bands, wherein quantity of the selected sub-carrier bands corresponds to the quantity of sub-carrier bands indicated by the acquired information. Fourth, information indicating channel quality of the selected sub-carrier bands is reported to the base station.

Abstract: Magnetic tracking systems and methods for determining the position and orientation of a remote object. A magnetic tracking system includes a stationary transmitter for establishing a reference coordinate system, and at least one receiver. The remote object is attached to, mounted on, or otherwise coupled to the receiver. The transmitter can include a set of three mutually perpendicular coils having a common center point, or a set of three coplanar coils with separate centers. The receiver can include a set of three orthogonal coils. The position and orientation of the receiver and the remote object coupled thereto is determined by measuring the nine mutual inductances between the three transmitter coils and the three receiver coils. The magnetic tracking system provides reduced power consumption, increased efficiency, digital compensation for component variation, automatic self-calibration, automatic synchronization with no connections between transmitter and receiver, and rapid low-cost implementation.

Abstract: Methods of forming a downlink beam in an adaptive antenna system of a communications system that may reduce inter-system and/or intra-system interference include receiving vectors of signals including signals transmitted by user terminals of the communications system and signals transmitted by transceivers of an independent communications system, obtaining spatial information for the user terminals of the communications system and the transceivers of the independent communications system, generating complex transmitting weights that form spatial nulls directed at the transceivers of the independent communications system, and transmitting a downlink communications signal using the complex transmitting weights. Related systems are also disclosed.

Abstract: A radio arrival direction estimation device that accurately estimates the arrival direction of radio waves from a desired tag, even when there are multiple antennas disposed at short intervals. When ID detection timing is provided from a timing detector (114) to a switch (201), relative amplitude/phase data related to the tag ID digital value “1” or “0” is obtained by an arrival direction estimation unit (125). One relative amplitude/phase datum is formed for each unit cycle in a first adder (202), which adds the relative amplitude/phase datum related to the tag ID digital value “1” to each element in a matrix, and a second adder (203), which adds the relative amplitude/phase datum related to the tag ID digital value “0” to each element in a matrix.

Abstract: A system that facilitates determination of a location of a mobile handset. The system includes three or more location measurement units that each correspond to a sector of the cell site. The location measurement units transmit location related information to a computation component. The computation component receives the location related information and performs a triangulation calculation on the information to define the location of the mobile handset.

Abstract: A method and apparatus for determining stream weights is provided herein. During operation, an uplink direction of arrival (DOA) and a downlink direction of departure (DOD) calibration procedure is implemented using uplink signals and GPS information from a subset of mobiles without the need of calibration circuitry at the base. Because the presented calibration procedure needs no new hardware it can be deployed in existing deployments with only a soft-ware upgrade.

Abstract: A system for establishing a wireless link from a wireless communication device (WCD) to at least one target device. The process of both identifying the target device and establishing a link to this device may incorporate the orientation and/or movement of the WCD into the procedure in lieu of the extensive use of traditional menu interfaces. A WCD may interpret a combination of orientation and/or movement as an approximate target device location that may be utilized to narrow the total population of all located devices into a subset containing those devices located within of near the approximate target device location. The subset of devices may be formulated and displayed as potential target devices for selection by a user. If any of the potential target devices are known by the WCD, a link may be established automatically.

Abstract: An electrically tilted antenna system with polarization diversity has a dual polarized, tilt adjustable antenna (32). The antenna (32) has dipoles (34, 36) of two orthogonal polarizations associated with independently adjustable electrical tilt angles. The tilt angles are implemented by relative delays between corporate feed input or output signals, the delays being introduced by an antenna tilt assembly (54). Two signal feeders (F21, F22) associated with different antenna polarizations connect the antenna tilt assembly (54) to a base station filter assembly (50): the base station filter assembly 50 routes transmit signals from base stations (BS21, BS22) to different antenna polarizations via respective feeders (F21, F22) and the antenna tilt assembly (54). This assembly also divides receive signals from feeders (F21, F22) between both base stations (BS21, BS22).

Abstract: A technique for determining the angles of arrival of signals incident on an antenna array from directions within an angular region of interest involves supplying outputs of antenna elements of the antenna array to a number of different weight generators. Each of the weight generators produces a set of beam-forming weights that maximizes a signal-to-interference ratio of a locally generated signal corresponding to a look angle that is outside the region of interest, with signals at different look angles being supplied to the different weight generators. An annihilation operator is determined from the sets of beam-forming weights generated by the weight generators and from beam-forming vectors representing the look angles of the locally generated signals used in the weight generators. The annihilation operator is applied to a group of beam-forming vectors representing angles within the region of interest to determine angles of arrival of signals within the region of interest.

Abstract: Aspects of a method and system for using a wireless local area network (WLAN) phase shifter for smart antenna beam steering are presented. Aspects of the system may enable determination of an angle of arrival (AOA) for signals received at a receiving station in a wireless network. Based on the AOA value, the receiving station may enable orientation of antenna in a smart antenna system. In a switched beam smart antenna system, antenna element(s) may be selected, which are most closely oriented toward the AOA. In an adaptive array smart antenna system, antenna beam may be steered, or reoriented, based on the AOA.

Abstract: A method and system for positioning mobile units using angle measurements taken by neighboring mobile units is disclosed. A selected mobile unit and mobile units in the vicinity of the selected mobile unit are selectively instructed to measure and report information related to the position of the selected mobile unit. The reported information is used to compute a position of the selected mobile unit.

Abstract: Aspects of a method and system for using a wireless local area network (WLAN) phase shifter for smart antenna beam steering are presented. Aspects of the system may enable determination of an angle of arrival (AOA) for signals received at a receiving station in a wireless network. Based on the AOA value, the receiving station may enable orientation of antenna in a smart antenna system. In a switched beam smart antenna system, antenna element(s) may be selected, which are most closely oriented toward the AOA. In an adaptive array smart antenna system, antenna beam may be steered, or reoriented, based on the AOA.

Abstract: Antennas with steerable antenna patterns and techniques for using such antennas are described. In accordance with the invention, antenna patterns with one or more NULLs are used. Through the use of digital control signals the antenna pattern is steered so that a source of signal interference, e.g., a multipath signal, will be located in a NULL. In this manner the received signal's S/N ratio can be maximized thereby facilitating demodulation. The techniques of the invention can be applied to television, computer devices, mobile devices and a wide range of other systems. Digital commands to control an antenna may include multiple information fields, e.g., a direction field, a channel field, a gain field and a polarity field. Antennas incapable of supporting the specified fields disregard information in fields which are not supported. Information in each supported field is decoded and used to adjust the corresponding antenna characteristic.

Abstract: A hybrid wireless network system is disclosed. The hybrid wireless network system includes an antenna array, an analog subsystem, and a digital subsystem. The antenna array at least includes two antenna elements. In the case of using multiple antenna elements to extend link range and coverage, a coarse-fine method is included for antenna elements selection. The analog subsystem calculates a difference signal and a sum signal based on the two RF signals. The analog subsystem includes step leveling devices. The digital subsystem estimates a direction-of-arrival (DOA) based on the sum signal and the difference signal. The step-leveling devices receive weights from the digital subsystem, in form of a feedback control, to apply the weights on the two RF signals respectively. The digital subsystem repetitively calculates new weights to update a beam pattern formed by the two RF signals until the DOA approaches null.

Abstract: A multi-antenna station with distributed antennas and capable of providing good performance for terminals distributed throughout the coverage area of the multi-antenna station is described. The multi-antenna station includes multiple antennas, a controller, and at least one transmitter unit. The multiple antennas are coupled to the multi-antenna station and include at least one remote antenna that is located away from the multi-antenna station. The controller selects a set of one or more antennas from among the multiple antennas for data transmission to a terminal. The at least one transmitter unit transmits data to the terminal via the set of one or more antennas.

Abstract: A polygonal cylindrically shaped phased array antenna forming a radar has an active aperture that focuses in any of one or more angular azimuth directions without inertia. It further includes adjacent multiple similar polygonal staves joined along their vertical edges to form a right regular polygonal cylinder. Each stave is further decomposed into flat panels, wherein each panel has a plurality of antenna elements positioned in a regular rectangular or triangular lattice. Each panel contains a beam forming network that electronically forms and steers an electromagnetic beam for purposes of transmission and subsequent reception. The panels optionally may operate as autonomous radars which when coherently combined form multiple larger antenna apertures, each capable of operating autonomously. A switching network allows transmit power and all requisite radar and control signals to be sent to and received from a selected set of panels anywhere on the polygonal cylinder.

Abstract: A multibeam transmitting/receiving apparatus is provided that is capable of increasing the accuracy of a direction in which a transmission beam is to be transmitted, with a simple arrangement. Signal power measuring units (8-1 through 8-L) of signal processing means (40-1 through 40-L) measure reception signal power levels averaged over a given time, using outputs from reception beam formers (5-1 through 5-L), and indicate the measured reception signal power levels to transmission antenna weight generator (30). Transmission antenna weight generator (30) generates transmission antenna weights, which has been weighted by a reception signal level, from a transmission antenna weight corresponding to reception signal power level P1 and a beam number B1 of a finger having a maximum reception signal power level, and a transmission antenna weight corresponding to reception signal power level P2 and a beam number B2 of a finger having the same path timing as the finger having the maximum reception signal power level.

Abstract: In a direction finding system, pluralities of signals provided by different sets of less than all of a plurality of arrayed antennas are code division multiplexed, downconverted by a single receiver, A/D converted and separated to derive signals that are processed to estimate the directions of arrival of the signals received by the different sets of antennas at different frequencies. The signals from different antennas are coded with different codes that have a common M-sequence and different phases for the different antennas. The derived signals are processed to detect the presence of signals and simultaneously demodulate and estimate the directions of arrival of signals by the antennas at the different frequencies. The different sets of antennas from which the received signals are provided for coding and multiplexing are selectively varied in accordance with the estimated directions of arrival and estimated magnitudes.

Abstract: A current flowing from a circuit section into an integrated antenna flows through a coil. When a pseudo up-link signal is outputted from a VICS (light) signal processing circuit to check a connection state of an integrated antenna, since a large current flows through a transmitting element for optical beacons of the integrated antenna, a drop voltage of the coil becomes large. When the drop voltage of the coil is within a prescribed range because of divided voltages of resistors, the antenna detection circuit determines that the integrated antenna is normal. In this case, since a large current flows into the coil, a coil having small impedance is used.

Abstract: Coverage areas for wireless networks are divided into a plurality of cells that are arranged in rows. Channel frequencies are assigned to cell sectors and associated with respective antenna axes. The antenna axes of adjacent rows are alternatingly rotated, thereby reducing co-channel interference. In an example, an available bandwidth is divided into twelve channel frequencies, so that a cell cluster includes four cells. Co-channel cells associated with half the channel frequencies are assigned to cells in the first row of cells, and the remainder are assigned to cells in the second row.

Abstract: Embodiments of the present invention provide a method and apparatus for all-polarization direction finding. The method and apparatus generally include acquiring measurements at least partially corresponding to an emitted signal and generated utilizing a blind signal extraction algorithm, forming an all-polarization cost function utilizing the acquired measurements, and determining an angle of arrival for the emitted signal utilizing the formed all-polarization cost function. Such a configuration enables angles of arrivals to be easily determined for signals having any polarization without using a multiple signal classification (MUSIC) algorithm.

Abstract: A method of determining the size of a sub-array for an antenna array is described. The method includes choosing a number of elements of a sub-array of antenna elements. Further, the method includes determining a direction of arrival of the signal using data from the sub-array. The method also includes computing weights for the antenna array. Further still, the method includes determining whether the size of the sub-array meets a predetermined criteria.

Abstract: A rotating antenna is used in a wireless system to impart a phase onto a received signal by electronically moving the effective receiving antenna location along a circular path such that the modulation phase angle indicates the bearing of the radio transmission and the gain of a signal transmitted by the antenna is increased in the direction of the received signal to enhance the link between transmitter and receiver. In order to simulate a rotating antenna, the antenna preferably comprises an antenna array having a plurality of antennae for use by one receiver. During reception of a signal from a remote transmitter, a scanner is adapted to scan through the plurality of antennae and in turn provide a signal received from each of the plurality of antennae to the receiver in the wireless system. The signal is modulated by virtue of the antenna rotation to include a Doppler frequency component.

Abstract: A mobile enforcement reader (MER) includes an antenna, a reader coupled to receive signals from the antenna and a control/display unit (CDU) coupled to the reader. The CDU selects a receive direction and processes signals provided thereto from the reader. When the MER and a transponder are in proximity, the MER interrogates the transponder and receives information related to toll payment. The MER allows enforcement officials to monitor payment by single occupancy vehicle (SOV) traffic for use of high occupancy traffic (HOT) lanes.

Abstract: A transmitter 1 transmits from a transmission antenna 7 a mixture signal containing a radio-frequency (RF)-band modulated signal, and a portion of power of a local oscillation signal used for frequency conversion. Meanwhile, a receiver 8 detects the transmitted signal by means of a reception antenna-detection section 9. In the reception antenna-detection section 9, a plurality of base unit reception circuits 11 are disposed. Each base unit reception circuit 11 includes a planar printed antenna 12 such as a patch antenna, an amplifier circuit 13 formed on a very small planar circuit by means of an MMIC technique, and a mixer circuit 14 serving as a square-law detector. Respective outputs of the base unit reception circuits 11 are power-mixed and fed to the IF signal demodulation section. The IF signal demodulation section 10 demodulate reception data.

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: Techniques for pre-correction of transmit signals are disclosed. In one aspect, a transmit antenna array configurable to generate multiple transmit beams is deployed. The parameters for configuring the antenna array are computed in response to channel estimates and a noise floor estimate made at the receiver. Information is transmitted in accordance with the multiple transmit beams, delayed as necessary, such that the multipaths may arrive time-aligned an in-phase at the receiver. In another aspect, pre-RAKE pre-correction is deployed by calculating Wiener weights. In yet another aspect, space-time diversity is deployed for calculating tap values for FIR filters used in transmission on the transmit antenna array. In yet another aspect, space only pre-correction is deployed. Various other aspects are also disclosed. These aspects have the benefit of reducing the interference experienced at a receiver, resulting in increased capacity, increased data throughput, and other system benefits.

Abstract: A design system designs a first antenna system in a communication system. The design system retrieves demographic information of customers from a first database system. The design system determines communication traffic based on the demographic information. The design system retrieves parameters of a second antenna system from a second database system. The design system determines an antenna system configuration for the first antenna system based on the communication traffic and the parameters of the second antenna system. The design system then determines a performance of the first antenna system in response to determining the antenna system configuration for the first antenna system.

Abstract: The present invention relates to estimating the Angle of Arrival (AoA) of a signal from a user equipment received at a base station of a wireless telecommunications network where the base station has a multi-beam antenna. A signal received from a user equipment is received by the each of the multiple beams of the antenna, and the two adjacent beams receiving the highest amplitude from the end user are selected. A ratio of functions of the amplitudes of the two selected beams, such as a ratio of the difference between the amplitudes of the two beams to the sum of the amplitudes is calculated and compared to a data store of ratios. The data store stores expected ratios corresponding to AoAs and the calculated ratio is compared to the pre-calculated expected ratios to extract an estimate of the AoA of the signal from the user equipment.

Abstract: A radar system with a radar sensor (10) which comprises a transmitting module (20), a receiving module (22) and a supply network (64), wherein the transmitting module (20) comprises a first plurality of partial antennas (26, 28, 30, 32, 34) and the receiving module (22) comprises a second plurality of partial antennas (46, 48, 50), and wherein the supply network (64) operates at least one partial antenna (30) of the transmitting module (20) together with at least one partial antenna (48) of the receiving module (22) in a first operating mode, to obtain a first, low angular resolution, and wherein the supply network operates one group of partial antennas (26, 28, 30, 32, 34) of the transmitting module (20) together with a group of partial antennas (46, 48, 50) of the receiving module (22) in a second operating mode to obtain a second high angular resolution.

Abstract: Coverage areas for wireless networks are divided into a plurality of cells that are arranged in rows. Channel frequencies are assigned to cell sectors and associated with respective antenna axes. The antenna axes of adjacent rows are alternatingly rotated, thereby reducing co-channel interference. In an example, an available bandwidth is divided into twelve channel frequencies, so that a cell cluster includes four cells. Co-channel cells associated with half the channel frequencies are assigned to cells in the first row of cells, and the remainder are assigned to cells in the second row.

Abstract: The present invention relates to an intraluminal magnetic resonance imaging (MRI) probe which may be used for intraluminal MRI. The present invention is sized sufficiently small to be inserted into a patient intraluminally. The probe of the present invention comprises a substrate having a dielectric constant in the range of 1-1000, and first and second conducting layers on each side of the dielectric. The present invention is configured to result in a distributed capacitance.

Abstract: Methods and apparatus are provided for determining a direction of arrival (DOA) (46) of a Radio Frequency (RF) signal (32) transmitted by a remote unit (22) in a wireless communication system (20). The methods comprise receiving the RF signal (32) with multiple antennas (34,36,38,40,42,44) of the antenna array (26) and determining a preliminary direction of arrival (DOA) (78) for the RF signal (32) received with the multiple of antennas (34,36,38,40,42,44) of the antenna array (26). The methods also comprise selecting a coefficient (80) for the antenna array (26) based at least in part upon the preliminary DOA 978), modifying the RF signal (32) with the coefficient (80) to generate a modified RF signal (82), and determining the DOA (46) of the RF signal (32) with the modified RF signal (82).

Abstract: A physically compact, wideband signal activity identification, demodulation and characterization, and direction finding device incorporates multiple and cascadable digital signal processing modules operating in asynchronous real time. The digital signal processing modules include a device for data buffering, a device for digital signal processing (DSP), and a device for high-speed data routing. The module device for data buffering is composed of, among other memory devices, a First In Tap Out (FITO) data buffer that may be accessed at any point for delay or faster than real time resynchronization by the DSP module device. The module device for digital signal processing function incorporates a general purpose digital processor for respective module calculation of overlapped hyperchannelization Fast Fourier Transforms (FFT).

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: A method and system are provided for predicting and detecting the crossing of two target tracks in a bearing versus time coordinate frame. The method/system use a series of periodic bearing measurements of the two target tracks to determine a bearing rate and a projected intercept with a bearing axis of the bearing versus time coordinate frame. A crossing time tc for the two target tracks is determined using the tracks' bearing rates and projected intercepts. A prediction that the two target tracks will cross results if a first inequality is satisfied while a detection that the two target tracks have crossed results if a second inequality is satisfied.