Abstract: One or more systems, devices, computer program products and/or computer-implemented methods of use provided herein relate to analysis of qubit coherence parameters of a physical qubit layout of a quantum computer. A system can comprise a pulse component for transmitting signals to a qubit, a readout component for receiving signals form the qubit, a memory that stores computer executable component, and a processor that executes the computer executable components stored in the memory. The computer executable components are executable to cause the pulse component to generate a first pulse to drive the qubit, cause the pulse component to generate a second pulse comprising an Autler-Townes off-resonant tone, and determine a probability relative to the qubit, in view of a shift of the qubit to a shifted frequency caused by the second pulse.

Abstract: A processor-implemented method for simultaneously tracking one or more objects includes receiving, via a dynamical system with a set of sensors, a first set of unlabeled measurements from one or more objects. Each of the measurements is a function of time. A set of candidate tracks is determined for the one or more objects. Probabilities of each of the first set of unlabeled measurements being assigned to each of the set of candidate tracks are computed. A track from the set of candidate tracks is determined for each of the one or more objects based on a joint probability distribution of track attributes and the probabilistic assignment of each of the first set of unlabeled measurements to each of the set of candidate tracks.

Abstract: Disclosed are techniques for environment sensing. In an aspect, a transmitter base station determines a configuration for a radio frequency (RF) sensing signal, the configuration determined based at least in part on coordination among a plurality of base stations, and transmits the RF sensing signal to at least one receiver base station based on the configuration. In an aspect, a receiver base station receives a configuration for an RF sensing signal, the configuration determined based at least in part on coordination among a plurality of base stations, receives, from at least one transmitter base station, the RF sensing signal, and detects at least one target object based, at least in part, on reception of the RF sensing signal.

Abstract: A computer includes a processor and a memory storing instructions executable by the processor to receive radar data including a radar pixel having a radial velocity from a radar; receive camera data including an image frame including camera pixels from a camera; map the radar pixel to the image frame; generate a region of the image frame surrounding the radar pixel; determine association scores for the respective camera pixels in the region; select a first camera pixel of the camera pixels from the region, the first camera pixel having a greatest association score of the association scores; and calculate a full velocity of the radar pixel using the radial velocity of the radar pixel and a first optical flow at the first camera pixel. The association scores indicate a likelihood that the respective camera pixels correspond to a same point in an environment as the radar pixel.

Abstract: Systems and methods for performing body scans to ascertain body measurements of a subject. A radar based scanner may be used to generate a three dimensional image of a subject as a point cloud map of electromagnetic radiation reflected from a target region. The point cloud may be mapped to a parametric model of a standard human shape. The mapping may be optimized by adjusting parameters of the parametric model. The resulting parameters of the optimized model may be used to indicate the body measurements of the scanned subject.

Abstract: Imaging systems, including radio frequency, microwave and millimeter-wave arrangements, and related methods are described. According to one aspect, an imaging system includes an antenna array, a position capture system configured to generate position information indicative of locations of one of the antenna array and the target at the first and second moments in time, and wherein the one of the antenna array and the target move between the first and second moments in time, a transceiver configured to control the antenna array to emit electromagnetic energy towards the target and to generate an output that is indicative of the received electromagnetic energy, a data acquisition system configured to generate radar data, processing circuitry configured to process the position information and the radar data to generate image data regarding the target, and an interface configured to use the image data to generate visual images regarding the target.

Abstract: Techniques for utilizing a depth completion algorithm to determine dense depth data are discussed are discussed herein. Two-dimensional image data representing an environment can be captured or otherwise received. Depth data representing the environment can be captured or otherwise received. The depth data can be projected into the image data and processed using the depth completion algorithm. The depth completion algorithm can be utilized to determine the dense depth values based on intensity values of pixels, and other depth values. A vehicle can be controlled based on the determined depth values.

Abstract: This document describes radar tracking with model estimates augmented by radar detections. An example tracker analyzes information derived using radar detections to enhance radar tracks having object measurements estimated from directly analyzing data cubes with a model (e.g., a machine-learning model). High-quality tracks with measurements to objects of importance can be quickly produced with the model. However, the model only estimates measurements for classes of objects its training or programming can recognize. To improve estimated measurements from the model, or even in some cases, to convey additional classes of objects, the tracker separately analyzes detections. Detections that consistently align to objects recognized by the model can update model-derived measurements conveyed initially in the tracks. Consistently observed detections that do not align to existing tracks may be used to establish new tracks for conveying more classes of objects than the model can recognize.

Abstract: An electronic device may include wireless circuitry with sensing circuitry that transmits radio-frequency sensing signals and receives reflected radio-frequency sensing signals. A mixer may generate a series of beat signals based on the sensing signals and the reflected sensing signals. The sensing circuitry may generate a beat phase based on an average of the series of beat signals, a set of phase values based on the series of beat signals, and a phase velocity based on the set of phase values. The sensing circuitry may resolve a phase ambiguity in the beat phase based on the phase velocity to identify a range between the electronic device and an external object. This way may allow the sensing circuitry to generate accurate ranges even in a low signal-to-noise ratio regime, such as when the external object is moving relative to the electronic device.

Abstract: A method of classifying terrain, terrain activity and materials through panchromatic imagery a module programmed to provide such classification and aerospace vehicles comprising such module is provided. Panchromatic images of known materials terrains and terrain activities are taken and processed to form a multiband texture cube, that due it amount of data, is stored as a computer data base. New panchromatic images of unclassified materials, terrains and/or terrain activities are processed and compared via computer with such database that allows for inexpensive, quick and efficient classification of such new images.

Abstract: Systems and methods for detecting degraded navigation sensors are based on a policy derived from a Partially Observable Markoff Decision Process (POMDP). Navigation parameters derived from the navigation sensors are provided to individual Kalman filters. A covariance of each of the filters is indicative of a probability of degradation of a sensor from which the navigation parameter is derived. Outputs of the Kalman filters are provided to a master filter. The master filter is compared to a criterion to determine whether there are indicia of a degraded sensor. If such an indicia are present, the Policy is consulted to determine which of the sensors are degraded. Consideration of degraded sensors when navigating a vehicle is inhibited.

Abstract: One-dimensional data obtained by performing a Fourier transform on a digitally converted frequency modulated continuous wave (FMCW) radar signal at every pulse repetition interval is input to a recurrent neural network (RNN) to find the probability of the existence of a target in each range index. The range indices, i.e., bit frequencies are selected based on the probability. In order to reduce the size of the RNN, windowing may be applied. In addition, a speed-index-specific coefficient value may be calculated by accumulating and performing a Fourier transform on the selected bit frequencies in which the target exists over a plurality of pulse repetition intervals. Thus, it is possible to calculate the speed of the target.

Abstract: An improved evaluation of radar signals, in particular radar signals received by a Uniform Linear Array (ULA) antenna. Through the application of a plurality of different beamformings to the radar signals, drops in the gain can be compensated by the beamforming.

Abstract: Methods and apparatus are disclosed regarding an e-commerce system that clusters customers based on demographic data and purchase history data for the customers. In some embodiments, the e-commerce system solves an Integer Program that accounts for the demographic data and purchase history data in order to identify a hyperplane that splits a selected cluster of customers.

Abstract: Method for providing reduced interference for at least two co-located FMCW (Frequency Modulated Continuous Wave) Doppler radars, each of said radars being used in a system to detect respective distances to and velocities of objects moving through space, can include a propagation determination step, in which expected electromagnetic wave propagation times are determined between pairs of radars; a sweep time offset synchronizing step, in which different respective sweep time offsets are selected, with respect to each radar in a first group of radars; and a sweep frequency offset synchronizing step, in which a second sweep frequency offset is selected with respect to a second group of radars, the second sweep frequency offset being relative to a sweep frequency pattern used for radars belonging to said first group. The invention also relates to a system and to a computer software product.

Abstract: A novel and useful two-stage radar return data processing mechanism for use in FMCW radar systems that divides the conventional frame into two portions. Two different frames are transmitted rather than one. The frames are transmitted consecutively one after the other. A low resolution ‘coarse’ frame is first transmitted that is fully processed in real time. Based on the results of the processing of the coarse frame, a plurality of targets of interest (TOIs) in the scene representing a subset of the received data is determined. Then a longer high-resolution ‘fine’ frame is transmitted and processed using the information obtained in the previous coarse fame. Using the TOI information obtained in the previous coarse frame, only a subset of the received data is processed. The non-processed portion is assumed to contain non-interesting information and is discarded or ignored thereby significantly reducing processing time.

Abstract: A subarray spatial averaging unit performs spatial averaging of correlation matrices by dividing a received signal of an array antenna to a plurality of subarrays having different shapes, and calculating these correlation matrices for the respective subarrays having different shapes. An eigenvalue expanding unit performs eigenvalue expansion of correlation matrices for the respective plurality of subarrays having different shapes after spatial averaging. A wave count estimating unit estimates an incoming wave count by integrating eigenvalues of the plurality of subarrays having different shapes obtained by the eigenvalue expanding unit.

Abstract: An electromagnetic wave field data processing method is provided and includes determining loss-free electromagnetic wave field data corresponding to electromagnetic wave field data according to the electromagnetic wave field data; performing first amplitude compensation on the electromagnetic wave field data and the loss-free electromagnetic wave field data; extracting waveform information; determining a first sequence corresponding to the electromagnetic wave field data and a second sequence corresponding to the loss-free electromagnetic wave field data which meet a preset condition respectively from the waveform information, determining time sequences corresponding to the first sequence and the second sequence; and determining an attenuation coefficient of the electromagnetic wave field data according to a first preset mode and performing second amplitude compensation on the electromagnetic wave field data according to the attenuation coefficient.

Abstract: Systems and methods for performing body scans to ascertain body measurements of a subject. A radar based scanner may be used to generate a three dimensional image of a subject as a point cloud map of electromagnetic radiation reflected from a target region. The point cloud may be mapped to a parametric model of a standard human shape. The mapping may be optimized by adjusting parameters of the parametric model. The resulting parameters of the optimized model may be used to indicate the body measurements of the scanned subject.

Abstract: An analysis of radar signals, in particular of radar signals, which are received by a plurality of ULA antennas. By applying different beam formations to the radar signals of the individual ULA antennas, beamforming is used to compensate for dips in the gain.

Abstract: A tracking device is configured to estimate a track for at least one possible target and is configured to receive incoming measurements and to process measurements and tracks. The tracking device includes a storage and a computational device. The tracking device is also configured to divide all measurements into a set of considered measurements and a set of unconsidered measurements for each passive track.

Abstract: An apparatus for detecting a target is disclosed. The apparatus of detecting a target includes: a frequency mixer configured to calculate a first beat frequency based on a transmitted signal and a received signal of first scanning and calculate a second beat frequency based on a transmitted signal and a received signal of second scanning performed with a predetermined time interval from the first scanning; a controller configured to extract a first moving component by comparing an up-chirp period frequency and a down-chirp period frequency of at least one of the first beat frequency or the second beat frequency; extract a second moving component by comparing up-chirp period frequencies or down-chirp period frequencies of the first beat frequency and the second beat frequency; and determine the moving target based on the first moving component and the second moving component.

Abstract: Doppler signal processing device for detecting an object according to a received wireless signal. The Doppler signal processing device includes a frequency analysis unit for generating a frequency domain signal vector according to at least one digital signal, an interference suppression unit for performing a suppression operation according to the frequency domain signal vector and a frequency domain interference estimation signal vector to generate an interference suppressed frequency domain signal vector, an interference estimation unit for generating the frequency domain interference estimation signal vector according to the frequency domain signal vector, a detection unit for generating a result signal according to the interference suppressed frequency domain signal vector, an error detection unit for optionally providing an error detection control signal to the interference estimation unit to adjust a rate of updating the frequency domain interference estimation signal vector.

Abstract: Systems and methods for operating radar systems. The methods comprise, by a processor: receiving point cloud information generated by radar devices; grouping data points of the point cloud to form at least one segment; computing possible true range-rate values for each data point in the at least one segment; identifying a scan window including possible true range-rate values for a largest number of data points; determining whether at least two modulus of the data points associated with the possible true range-rate values included in the identified scan window have moduli values that are different by a certain amount; determining a new range-rate value for each data point of the segment, when a determination is made that at least two modulus of the data points do have moduli values that are different by the certain amount; and modifying the point cloud information in accordance with the new range-rate value.

Abstract: A method for producing an interference reduced radar image comprises receiving a measured sequence of beat signals; identifying one or more interference segments within the measured sequence of beat signals, an interference segment being a segment subject to an interference; doctoring the measured sequence of beat signals by creating a doctored representation of the measured sequence of beat signals in the form of a matrix Y; creating a doctoring mask representing the doctoring of the measured sequence of beat signals, the doctoring mask being a matrix M; and estimating a reconstructed range-doppler image {circumflex over (X)} from Y and M, wherein the reconstructed range-doppler image is a range-doppler image of Y which is deconvolved using M; such that doctoring the measured sequence of beat signals at least partially removes interference effects and estimating a reconstructed range-doppler image at least partially removes image artefacts created by the doctoring.

Abstract: A sensor system, having sensor elements for sensing at least to some extent different primary measured variables or use different measurement principles. A signal processing device evaluates the sensor signals from the sensor elements at least to some extent collectively and rates the information quality of the sensor signals. The signal processing device further provides a piece of information about the consistency of at least one datum of a physical variable, wherein this datum of the physical variable is calculated, at least to some extent, on the basis of the sensor signals from sensor elements that sense this physical variable directly or from the sensor signals from which it is possible to calculate this physical variable. The information about the consistency of this datum of this physical variable is calculated at least on the basis of the directly or indirectly redundantly present sensor information.

Abstract: A communication device can be configured to detect radar signals within an operating channel. The communication device can include a mixer, filter, scanning and spreading circuit and a radar signal detector. The mixer can be configured to modulate a received communication signal based on an oscillating signal to generate a modulated signal. The filter can have a first bandwidth and be configured to filter the modulated signal. The scanning and spreading circuit can be configured to control the oscillating signal to scan an operating channel having a second bandwidth. The second bandwidth can be greater than the first bandwidth. The radar signal detector can be configured to detect a radar signal within the scanned operating channel.

Abstract: A method, system, and computer program are described for identifying the presence of narrowband signals within a wide instantaneous bandwidth by exploiting the spatial diversity of the received signals using an array aperture to provide detection capability. For example, the method includes receiving and channelizing digitized signals into signals with a narrow bandwidth of interest. The method further includes estimating covariance matrices associated with the signals, determining a set of Eigenvalues for the covariance matrices, and analyzing each Eigenvalue to determine a rank change estimate. The method further includes identifying one or more of the signals that have a positive rank change estimate, computing a beam forming weight and direction estimate for each signal that has a positive rank change estimate, and outputting an indication of the signals that have a positive rank change estimate including one or more of fine timing information, the beamforming weights, and the direction estimate.

Abstract: The invention relates to a method in a radar system, wherein: in a first non-coherent transmitting-receiving unit (NKSE1), a first signal (sigTX1) is generated and is transmitted, in particular emitted, via a path (SP); in a further, in particular second non-coherent transmitting-receiving unit (NKSE2), a first signal (sigTX2) is generated and is sent, in particular emitted, via the path (SP); in the first transmitting-receiving unit (NKSE1), a comparison signal (sigC12) is formed from the first signal (sigTX1) of the first transmitting-receiving unit and from such a first signal (sigTX2) received from the further transmitting-receiving unit (NKSE2) via the path (SP); and in the further transmitting-receiving unit (NKSE2), a further comparison signal (sigC21) is formed from the first signal (sigTX2) of the further transmitting-receiving unit and from such a first signal (sigTX1) received from the first transmitting-receiving unit (NKSE1) via the path (SP), wherein the further comparison signal (sigC21) is tra

Abstract: The communication method using an almost periodic function code includes using, for modulation, almost periodic function codes the number of which is in accordance with the number of users or the number of channels, among K almost periodic function codes. Where k is an integer from 1 to K and is an identifier for identifying each of the K almost periodic function codes, a parameter that determines each of the K almost periodic function codes is represented by ?+(k?1)/K. The symbol K is N or 2N, where N is a code length of each almost periodic function code. The symbol ? is a real number greater than 0 and less than 1/N.

Abstract: Disclosed is a method and apparatus for detecting an object using a radar in a vehicle, wherein object detection is performed by generating a transmission signal using a code sequence, receiving an echo signal reflected from an object, and detecting the object based on the echo signal and the code sequence.

Abstract: Embodiments of the present invention implement a novel methodology for processing radar image data from a radar system having one or more transmitter and receiver antenna pairs. The novel methodology deliberately operates on spectrally-notched radar data. It uses a specially-adapted version of the CLEAN algorithm to mitigate the effects of frequency-band notching. Following that, it performs a non-linear sidelobe-reduction algorithm to further eliminate artifacts and produce radar imagery of much higher quality. In some cases, it exploits a specific version of the recursive sidelobe minimization (RSM) algorithm which operates in the frequency and aperture (spatial) domain.

Abstract: An unmanned aircraft navigation system includes a master navigation device, a slave navigation device, and a controller. The master navigation device includes at least one measurement component. The slave navigation device includes at least one measurement component configured to provide a redundancy support for the at least one measurement component of the master navigation device. The controller is configured to effect a navigation using the at least one measurement component of the master navigation device and the at least one measurement component of the slave navigation device.

Abstract: A tracking device estimates a track for at least one possible target and is configured to receive incoming measurements and process measurements and tracks. The device has a storage device and a computational device and an association module to calculate an association between a measurement and a track. The device further has an output module to output a sequence of track updates from an assignment module maintaining a set of active tracks using the association module as a function of active tracks and the incoming measurements to calculate associations, containing possible track updates and deciding which track updates to keep in the active tracks set and which to add to a passive tracks set. Computations on the passive tracks may be deferred until at least one passive track handling criterion is fulfilled. The computational device may activate and transfer a passive track from the passive set to the active set.

Abstract: A method for detecting radial deformation in a winding of a transformer may include synthetic aperture radar (SAR) imaging of the winding using ultra high frequency (UHF) electromagnetic signals in a first instance of the winding to obtain a first image of the winding; SAR imaging of the winding using UHF electromagnetic signals in a second instance of the winding to obtain a second image of the winding; and comparing the first image of the winding and the second image of the winding to detect a radial deformation in the winding. The UHF electromagnetic signals may be transmitted as a plurality of successive sinusoidal signals, where frequencies of the successive sinusoidal signals gradually change from a first frequency to a second frequency.

Abstract: A wireless power transmitter configured to wirelessly transmit power to an electronic device is provided.

Abstract: A method performed by an apparatus included in a vehicle to detect an object using a radar includes: propagating, in a normal mode period of an operating period for detecting objects, a normal mode transmission signal generated based on a default code sequence including at least two codes; receiving a normal mode reception signal in the normal mode period; detecting, in the normal mode period, an object based on the default code sequence and the normal mode reception signal; receiving a listening mode reception signal in a listening mode period of the operating period; acquiring a correlation between the listening mode reception signal and the default code sequence; and changing the default code sequence based on the correlation.

Abstract: Methods and systems for generating radar data are disclosed. A scene is defined based on map and route information, where the scene includes one or more objects. Values are assigned to a set of object parameters that describe each of the objects in the defined scene to produce one or more sets of object parameters describing the object(s). The defined scene and the set(s) of object parameters are used to generate scattering data associated with the defined scene. Based on the scattering data and the map and route information, radar data is generated that includes radar information of each object in the defined scene, where the generated radar data is used to train a predictive model to classify each of the identified objects.

Abstract: Whether or not motion compensation is necessary is determined for each of received radio wave signals acquired through observation on the basis of information on a difference between an planned trajectory and an actual trajectory of a platform (103), and a motion compensation process is performed on the received radio wave signals for which the motion compensation is determined to be necessary. An image generation process is performed on the received radio wave signals on which the motion compensation process has been performed and the received radio wave signals on which the motion compensation process has not been performed depending on the results of determination, so that a SAR image of an observation object is generated.

Abstract: Methods and systems including computer programs encoded on a computer storage medium, for receiving, from a camera, a set of images in which the camera detected a particular event based on a first set of camera settings, determining that false detections in the set of images made by the camera based on the first set of camera settings were caused by localized errors, and in response, generating a second set of camera settings based on the localized errors and providing the second set of camera settings to the camera.

Abstract: A receiving device comprises an analogue reception filter designed for a given frequency band included in the entire operating band of radar, the device further comprising a digital filter able to separate the received signals depending on their frequency, one portion of the frequency band of the given frequency band allocated to the radar reception function and another portion allocated to an RESM reception function.

Abstract: A system and method for rank estimation of electromagnetic emitters is provided. One aspect of the disclosure provides creating a graph of angles of arrival (AoAs) versus range and using a polynomial curve fit against the graph to determine a rank estimation of electromagnetic emitters. Another aspect of the disclosure provides using a search over parameters of the multiple polynomial curve fits, for each hypothesized rank, to optimize the rank estimation results. This search may be a greedy search to improve speed of convergence. Another aspect of the disclosure provides a metric ‘score’ to select the highest probability rank (number of emitters) based on the agreement between the multiple polynomial curve fits and residual AoA errors.

Abstract: A dual slot SIW antenna unit includes a first substrate, a conductive layer, plural unit radiation members, a second substrate, a ground conductive layer, and two first conductor pillars. The plural unit radiation members are disposed in parallel on the conductive layer, and each unit radiation member includes at least a pair of slots that are disposed in parallel. The two first conductive pillars are disposed between two neighboring unit radiation members and electrically connect the feed routing layer and the conductive layer. A dual slot SIW antenna array module is also disclosed. By use of the dual slot structure, more radiation members are allowed to be included in a limited square measure for improving the antenna gain.

Abstract: Systems, methods and software products optimize installation and operation of an object tracking system. Performance of the athlete tracking system is continually monitored and optimized based upon one or more of: statically positioned tags, grouping tags within two or more tag sets to assign ping rates, selecting receiver configuration and aim dynamically based upon environmental and situational conditions. Tracking tags are improved to facilitate coupling of the tag to an athlete and may be self-configurable. A trackable protection pad allows a tracking tag to be positioned substantially horizontal when the athlete is competing. A data replay tool replays location tracking information in chronological order and visually plots location of tracking tags and errors in the determined location. A tag manager automatically configures the tracking tags. A robotic vehicle automated installation of the object tracking system.

Abstract: A vehicle camera system and method for operating a vehicle camera system comprising a vehicle camera with communication capabilities. The vehicle camera operating in conjunction with other components to provide information to users. The vehicle camera system compiles information from multiple components into a single repository of video recordings with information, such as location information, vehicle status and diagnostic information, alert information and other information.

Abstract: A system and methods for RF (Radio Frequency) penetration imaging of one or more objects in a medium, the system comprising: a generation and reception unit configured to generate and receive RF signals; an antenna array configured to transmit/receive the RF signals, the antenna array comprises a plurality of antennas: and a processor in communication with said antenna array, said processor is configured to analyze said RF signals and estimate the distance between the antenna array and the object, and in addition the relative orientation between the antenna array and the medium surface.

Abstract: A method for filtering spatial error from a measurement vector is provided to correct for roll, pitch and yaw angular motion. The method includes the following operations: Establish an unstabilized body reference frame. Convert the measurement vector to an unstabilized state vector xU in the unstabilized body reference frame. Establish a stabilized East-North-Up (ENU) reference frame. Calculate an unstabilized pre-transform covariance matrix MU from position variance of the body reference frame. Measure roll, pitch and yaw in the body reference frame as respective angle values (r, p, w). Calculate a transform matrix T between the body reference frame and the ENU reference frame. Calculate a stabilized data vector xS=TxU from the transform matrix and the unstabilized state vector. Calculate a measured angle error sensitivity matrix MA from the angle values. Calculate a tri-diagonal angle error component matrix ME with square values of angle variance of the body reference frame.

Abstract: A communication device for mounting to an infrastructure, the communication device being configured for communication with a remote communication device via a directive antenna main lobe, the communication device comprising a sensor module configured to measure a movement of the communication device relative to a reference orientation.

Abstract: A wireless communication device comprises at least one antenna array configured to receive a radio signal; a first compressor configured to determine a first compression operator based on a predetermined set of receive configurations for the antenna array, and to apply the first compression operator to the radio signal to generate a first compressed signal; a second compressor configured to apply a second compression operator to the first compressed signal to generate a second compressed signal; a channel estimator configured to determine a channel covariance of the radio signal, determine at least one eigenvector of the channel covariance to obtain a second compression operator, and provide the second compression operator to the second compressor; and a baseband processor configured to receive the second compressed signal from the second compressor and to process the second compressed signal to obtain output data.

Abstract: An apparatus for processing a signal by means of electromagnetic waves according to one embodiment of the present invention can, when a radio frequency (RF) signal is radiated onto a medium through any one of a plurality of channels, simultaneously receive the radiated RF signals which have been reflected or scattered by the medium or have penetrated the medium through the plurality of channels other than the channel through which the RF signal has been radiated.