Abstract: A channel estimator and a channel estimation method are provided. The channel estimator comprises a storage module, for storing a plurality of channel responses of first pilot signals over a plurality of continuous pilot sub-channels, and a plurality of channel responses of second pilot signals over a scatter pilot sub-channel; and a calculation module, for calculating a channel response at a time point without a pilot signal over the scatter pilot sub-channel according to the channel responses of the first pilot signals and the channel responses of the second pilot signals.

Abstract: A cable modem executes periodic ranging with a cable modem terminal system and records a time point at which the periodic ranging is completed. The cable modem obtains an un-ranging time interval during which the cable modem terminal system permits the cable modem not to execute periodic ranging with the cable modem terminal system, and sets a sleep time interval during which the cable modem does not execute periodic ranging with the cable modem terminal system according to the un-ranging time interval. Then, the cable modem shuts off a power amplifier in the cable modem in the sleep time interval if the cable modem does not transmit packets during the preset time interval before the recorded time point.

Abstract: A receiver includes a demodulator that demodulates a modulation wave modulated according to orthogonal frequency division multiplexing (OFDM). The demodulator includes an interference wave detector that detects that received modulation wave includes interference wave when received power of each sample of the received modulation wave exceeds a threshold, and upon the detection, executes replacement processing of replacing a received signal exceeding the threshold with a predetermined value, a first interference wave power estimation unit configured to estimate interference wave power included in an OFDM symbol included in the received modulation wave on the basis of the number of samples that have been subjected to the replacement processing, and a demodulated data generator that demodulates the received modulation wave by executing demodulation processing of demodulating the received modulation wave that has been subjected to the replacement processing on the basis of the interference wave power.

Abstract: A double data rate serial encoder is provided. The serial encoder comprises a mux having a plurality of inputs, a plurality of latches coupled to the inputs of the mux, an enabler to enable the latches to update their data inputs, and a counter to select one of the plurality of inputs of the mux for output. In another aspect, the mux provides a glitch-less output during input transitions. The mux includes an output selection algorithm optimized based on a priori knowledge of an input selection sequence provided by the counter.

Abstract: Various systems and methods for probing a communication channel. These systems and methods transmit an error vector probe packet from a first transmitter while a second transmitter is active and transmitting. A network device may receive the error vector probe packet and measure an error vector magnitude based on the received error vector probe packet. Using the error vector magnitude, the network device estimates channel characteristics such as signal-to-noise ratio, data capacity, etc. The transmission can occur when more than one transmitter is active and transmitting. At least some of the other transmitters are active and transmit an analog zero signal, e.g., all digital zeros on the input to the digital-to-analog converter of a network device when an error vector probe packet is transmitted.

Abstract: A method and system that provides for execution of a first calibration sequence, such as upon initialization of a system, to establish an operation value, which utilizes an algorithm intended to be exhaustive, and executing a second calibration sequence from time to time, to measure drift in the parameter, and to update the operation value in response to the measured drift. The second calibration sequence utilizes less resources of the communication channel than does the first calibration sequence. In one embodiment, the first calibration sequence for measurement and convergence on the operation value utilizes long calibration patterns, such as codes that are greater than 30 bytes, or pseudorandom bit sequences having lengths of 2N?1 bits, where N is equal to or greater than 7, while the second calibration sequence utilizes short calibration patterns, such as fixed codes less than 16 bytes, and for example as short as 2 bytes long.

Abstract: A method of operation of a communication system includes: calculating a shift distance of a received signal having a distortion; calculating an approximate likelihood of the received signal matching a transmitted signal from the shift distance; determining a bias factor from the distortion; and selecting a determined modulation maximizing a combination of the approximate likelihood and the bias factor for communicating with a device.

Abstract: Signal received in a wireless network are detected by arranging samples of the signal in a set of windows. For each window, estimating interference, an average signal, noise and interference ratio (SINR), and a channel. For each window, also classifying a type of a process of a set of processes of a receiver. Then, selecting the process for each windows according to the type to detect the signal in the window.

Abstract: Transceiver calibration is a critical issue for proper transceiver operation. The transceiver comprises at least one RF transmit chain and one RF receive chain. A closed loop path is formed from the digital block, the RF transmit chain, the substrate coupling, the RF receive chain back to the digital block and is used to estimate and calibrate the transceiver parameters over the operating range of frequencies. The substrate coupling eliminates the need for the additional circuitry saving area, power, and performance. In place of the additional circuitry, the digital block which performs baseband operations can be reconfigured into a software or/and hardware mode to calibrate the transceiver. The digital block comprises a processor and memory and is coupled to the front end of the RF transmit chain and the tail end of the RF receive chain.

Abstract: In a method for carrying out bidirectional communications between a first electronic unit and a second electronic unit, a clock signal and an input signal synchronized with the clock signal are transmitted from the first electronic unit to the second electronic unit, and the second electronic unit transmits a response sequence in an output signal to the first electronic unit. In addition, an unambiguous test sequence is generated in the second electronic unit and transmitted to the first electronic unit prior to the response sequence in the output signal, a time sequence between the test sequence and the response sequence in the output signal making it possible to take into account a time delay between the first electronic unit and the second electronic unit.

Abstract: Provided is a communication testing circuit that includes a transmitting unit including a spread spectrum clock generator that generates a modulated clock signal by modulating a reference clock signal, a pseudo-random binary sequence generator that generates a pseudo-random pattern, and a signal generator that generates a transmission signal by modulating the pseudo-random pattern based on the modulated clock signal, a receiving unit including a clock and data recovery circuit that receives the transmission signal and recovers the pseudo-random pattern from the transmission signal, and a detector that compares the recovered pseudo-random pattern with a preset pseudo-random pattern and outputs a signal indicating error information, and a control unit that counts a number of errors from the signal indicating error information input from the receiving unit and decides a timing margin based on a counting result.

Abstract: Embodiments of the present disclosure provide a reporting allocation unit, an indicator interpretation unit and methods of operating a reporting allocation unit and an indicator interpretation unit. In one embodiment, the reporting allocation unit includes an indicator configuration module configured to provide reporting interval and offset values of corresponding rank and channel quality indicators for user equipment. The reporting allocation unit also includes a sending module configured to transmit the reporting interval and offset values to the user equipment.

Abstract: Provided is a method for acquiring continuous physical signal such as temperature, pressure and the like. The method comprises the following steps: inputting a voltage signal u representing continuous physical signal; obtaining a sampled signal uk of an analog voltage through an analog sampling channel (1), wherein the sampling frequency is f?h; performing digital low-pass filtering on the uk (6) to obtain a voltage signal ?k subjected to low-pass filtering, and resampling the ?k to obtain a resample signal ?j, wherein the resampling frequency f?y is the same as the sampling frequency required by an application terminal and the sampling frequency f?h is M times of the resampling frequency f?y; and storing and outputting the resample signal ?j to the application terminal. Provided also is a corresponding device.

Abstract: Disclosed are a signal compression apparatus and method for dynamic compressive sensing, including: a signal input unit configured to simultaneously output an input signal, and generate and output a linear measurement reference signal based on the input signal; a linear transform unit configured to receive the linear measurement reference signal and variably generate a linear measurement matrix value according to the linear measurement reference signal; a signal compressor configured to output a compressed signal for the input signal based on the generated linear measurement matrix value; and a signal processor configured to reconstruct the compressed signal and perform spectrum sensing of the input signal.

Abstract: Four (=M) transmission information signals are output from transmission information generating unit to linear transform unit, where they are transformed into synthesis signals by linear transform expressed by multiplication by a 2×4 matrix having complex numbers as elements. Signal processors perform signal processing corresponding to the modulation technique of test target on synthesis signals. On the resultant signals, 2×2 channel processing unit performs 2×2 pseudo channel processing, thereby forming equivalent M×N channels. Parameter setting unit sets information necessary to acquire desired M×N channel characteristics as the synthesis characteristics of linear transform unit and N×N channel processing unit.

Abstract: Improved performance testing of a wireless device is disclosed. The system is particularly suited to testing devices having multiple antennas. The device under test (DUT) is placed in a reverberation chamber with antennas for transmission of a test signal to the DUT. The number of antennas deployed in the reverberation chamber and placement of those antennas is selected such that no line-of-sight transmission component exists from test system antenna to DUT antenna, and the number of antennas deployed in the reverberation chamber is greater than the spatial rank of the signal. The antennas are driven by a programmable channel emulator capable of generating fading, correlation, delay, Doppler and other channel condition phenomena. Furthermore, the antennas are driven individually by a plurality of independent fading processes.

Abstract: The present invention provides a test device and a method enabling automatic detection of an imbalance in a power level of a channel. The test device includes a tuner, a power-level measurement system, and an evaluation unit. According to the method, a test channel is selected from a plurality of channels, by means of the tuner. A power level of the test channel and a total power level of the plurality of channels are measured, by means of the power-level measurement system. A ratio of the total power level of the plurality of channels to the power level of the test channel is then evaluated, by means of the evaluation unit, to detect an imbalance in a power level of the test channel.

Abstract: Embodiments of the present invention provide a rate matching method and apparatus. The method includes: receiving bit data of a first, a second, and a third input subblock, inserting dummy data into bit data in each subblock to respectively form even-numbered rows and odd-numbered rows of a matrix to be buffered for each subblock; inputting bit data of the even-numbered rows in the even-numbered row buffer and bit data of the odd-numbered rows in the odd-numbered row buffer of each subblock to a second buffer, and forming a matrix by using the bit data of the even-numbered rows and the bit data of the odd-numbered rows; controlling the second buffer to send data at the specified address; selecting data sent by the second buffer; and deleting the dummy data from the selected data to obtain valid output data.

Abstract: Spectrum sensing methods and systems for detecting spectrum holes for use in cognitive radio secondary transmissions are disclosed. In one method, an indication of an assignment of a set of subcarriers to a primary user is received. The method further includes determining multitaper spectral estimates for at least a subset of the set of subcarriers based on the assignment of the set of subcarriers to the primary user by processing samples for the at least a subset of the set of subcarriers. In addition, a test statistic that is based on the multitaper spectral estimates is compared to a threshold to determine whether the set of subcarriers is utilized for primary transmissions to the primary user. Moreover, data signals are received on at least one of the subcarriers in the set of subcarriers if the set of subcarriers is not utilized for primary transmissions to the primary user.

Abstract: Methods and devices related to channel estimation for a communication system comprising a plurality of communication connections are provided. For channel estimation, test sequences are used having three different elements, for example ?1, 0 and +1.

Abstract: A test system for testing wireless circuitry in an electronic device is provided. The test system may include a test host and a tester. The tester may provide radio-frequency test signals to a device under test (DUT). The DUT may include radio-frequency decoding circuitry that processes the test signals using a communications protocol and digital demodulator circuitry that processes the test signals without using the communications protocol. The digital demodulator circuitry may include transformation circuitry that performs fast Fourier transforms on the test signals to create frequency-domain performance data. The test host may compute a noise floor and signal-to-noise ratio based on the frequency-domain performance data. The test host may compare the computed noise floor and signal-to-noise ratio to predetermined thresholds to characterize the radio-frequency performance of the wireless circuitry.

Abstract: The disclosure relates to a receiver system that employs multiple instances of a DC compensation system to reduce DC offsets in a receiver path. The receiver has a receiver front end configured to receive an RF input signal and to operate on the RF input signal according to a plurality of receiver states to generate a baseband signal having a DC offset that is based upon the plurality of receiver states. A DC offset compensation circuit implements a plurality of instances of DC offset compensation components that respectively generate an estimated DC offset corresponding to a receiver state. A controller controls the receiver state of the receiver front end and operates the DC offset elimination circuit to selectively apply one of the plurality of DC compensation components to the corresponding baseband signal based upon the receiver state.

Abstract: Methods and systems to mitigate impulse interference in an OFDM QAM signal. A per-symbol noise measure, or quality measure (QM) is computed for a symbol k as a MSE of distances between carriers in the symbol and points of corresponding QAM constellations. MSE(k) is averaged over multiple symbols to compute a background signal QM, AVG_MSE(k). If MSE(k) exceeds AVG_MSE(k) by a moderate amount, symbol k may be moderately affected by impulse interference, and per-carrier SNR estimates are downgraded for all data carriers in symbol k, prior to LLR computation. SNR downgrading may be linear or step-wise based on an extent to which MSE(k) exceeds AVG_MSE(k). If MSE(k) exceeds AVG_MSE(k) by a significant amount, symbol k may be significantly affected by impulse interference, and LLRs may be set to indicate that all data carriers are erased in symbol k.

Abstract: A channel estimating method and device are provided. The method includes: performing multi-path searching on a pilot channel, and performing interpolation on a channel estimation value at a radial position of the multi-path searching (101); performing raised cosine de-convolution on the channel estimation value that undergoes the interpolation (102); acquiring the channel estimation value at each radial position in the pilot channel according to the channel estimation value that undergoes the raised cosine de-convolution and a sample deviation acquired by performing the multi-path searching (103). The channel estimating method and device eliminate the sample deviation of the channel estimation value, improve the demodulation performance, and evidently reduce the operation workload.

Abstract: A method is provided for determining whether transmission signals are present in received signals, the method comprising: receiving a first signal via a first radio resource; receiving a second signal via a second radio resource; determining whether a first transmission signal is present in the received first signal based on the received second signal; and determining whether a second transmission signal is present in the received second signal based on the received first signal.

Abstract: A device and a method for processing an input data of an protective relay, even in case that data stored in an accumulation buffer of the protective relay is damaged due to noises, etc., that can recover it and carry out a normal measurement are provided, the invention includes a digital signal processing part comprising inputting a sampled digital data to a digital signal processing part, counting and accumulating frequency of the inputted data, comparing the accumulated value with a value of a period, inputting a value of an update accumulation buffer to a measurement accumulation buffer and initializing the update accumulation buffer if the counted accumulation frequency is equal to the value of one period; and performing an RDFT (Recursive Discrete Fourier Transform) operation on the inputted digital data to dually buffering the measurement accumulation buffer and the update accumulation buffer.

Abstract: In described embodiments, a transceiver includes an eye monitor and margin detector having one or more samplers with corresponding logic. One or more programmable provisioning parameters are defined based on a pre-defined minimum target operating margin for acceptable noise and jitter margins. For example, two programmable provisioning parameters, phase and voltage, correspond with thresholds for margin samplers placed within the eye. Initially, the transceiver applies equalization, after which an inner eye of the transceiver, as detected by the eye monitor, is relatively open with some margin for supporting channels. If the receiver margin goes below this target margin, the eye closes, which is registered by the samplers. In the presence of spectrally rich input data, if the receiver margin goes below this target margin, an updated adaptation of equalizer or other circuit parameters might be initiated; else, adaptation is not generally required.

Abstract: A method for determining a corrected estimated variance representative of the condition of reception of signals representative of symbols transferred by an emitter to a receiver through a communication channel. The method includes, executed by the receiver, producing an estimation of the variance by a Wiener channel estimator comprising a linear filter of which coefficients are determined at least from a given average signal to interference plus noise ratio value. The method further includes, executed by the receiver, multiplying the estimation of the variance by a correction factor. The value of the correction factor, being dependent at least on the number of coefficients of the linear filter of the Wiener channel estimator.

Abstract: One or more communications parameters associated with a multiple input, multiple output (MIMO) signal transmitted by a transmitter are identified. The one or more communications parameters include one or more of (i) a number of receive antennas via which the MIMO signal is received, (ii) a number of spatial streams in the MIMO signal, and (iii) a signal to noise ratio (SNR) corresponding to the MIMO signal. A particular data detection technique of a plurality of data detection techniques employed by a receiver is selected in accordance with at least one of the one or more communications parameters.

Abstract: A method for quantification of the desynchronization between the clocks of two medical devices communicating wirelessly, for example, by HBC signals. The devices are separately clocked by slow clocks (CLK1/32k, CLK2/32k) and include selectively activated fast clocks (CLK1/10M, CLK2/10M). The method comprises: a) on a predetermined transition (T1) of a slow clock, transmission by one device of a synchronization query signal (SYNC) to the other device, b) counting of the pulses of the activated fast clock to detect a predetermined transition (T3) of the first slow clock, then c) transmitting from the other device to the first device a response signal (D1) and d) upon reception of the response signal, computing a temporal shift (OFFSET) according to the result (D1, D2) of the counting of the pulses of the fast clock. Two fast clocks, one on each device, also can be used.

Abstract: The object of the present invention is to provide a mobile terminal tester which can reduce the production cost from that of the conventional mobile terminal tester.

Abstract: A method of identifying an electronic or electromechanical system includes: applying at least one noise signal (u) as input to the system, applying an output signal of the system to a one-bit analog digital converter, acquiring a signal at the output of the converter, carrying out an estimation of the output of the system with aid of performing an estimation (?) of the impulse response of the system. The estimation (?) of the impulse response includes: iterative calculation of a plurality of nh elements (J0, . . . , Ji, . . . , Jnh?1) of a given criterion (J), each element including, respectively: at least one term of correlation between the signal at the output of the converter and the noise signal.

Abstract: Provided is a test apparatus that tests a device under test, comprising: a test module that tests the device under test by sending signals to and receiving signals from the device under test; a test controller that controls the test module; and a network that transmits communication packets between the test module and the test controller, wherein at least one of the test module and the network transmits to the test controller a usage state packet that indicates a usage state of a communication buffer that buffers the communication packets.

Abstract: Devices and methods for serial loopback testing in an integrated circuit (IC) are provided. To implement loopback testing, an equalizer stage of a receiver of the IC is powered down. In addition, the common-mode voltage of the equalizer stage is reduced and/or a bulk node of the equalizer stage is connected to ground. Doing so may reduce the impact of capacitive coupling from the input pins of buffer, thereby improving the quality of the loopback output signal.

Abstract: An evaluation device is configured to provide a transceiver system with performance information thereof. The transceiver system models a channel between a transmitter and a receiver thereof using Nakagami distribution with a fading parameter. The evaluation device includes a setting module operable to set an average signal-to-noise rate (SNR) for the channel between the transmitter and the receiver, a computing module operable to estimate a symbol error rate related to a signal received by the receiver from the transmitter based upon the fading parameter and the average SNR, and an output module operable to provide the average SNR and the symbol error rate as the performance information of the transceiver system.

Abstract: A test and measurement instrument includes an input for receiving an input test signal and a separator that separates a data array of the input test signal into a number of different data bins. Each data bin includes a number of data points. A selector is included that determines whether the data points within a present bin of the total bins represent signal or noise. When the present bin contains noise, a processor generates a first output for the present bin. Instead, when the present bin contains signal, the processor generates a second output for the present bin. The bin outputs can then be combined to make an output array, such as a waveform display, for the instrument.

Abstract: A device for calibrating a digital communication station uses an initial ranging procedure for measuring channel parameters in a communication channel. The device comprises a communication emulator, a measuring device, and a calibrator. The communication emulator transmits a signal to the communication station which transfers the communication station into an initial ranging mode. The measuring device measures parameters of the signal transmitted by the communication station during an initial ranging cycle. From these measurements the calibrator calculates the necessary calibration adjustments to the communication station and adjusts it accordingly.

Abstract: A system and method for physical layer device enabled clock diagnostics. The physical layer device can monitor the performance of a clock recovery module. Performance monitoring can be performed on the output clock signal or the control components used to generate the output clock signal. In one embodiment, the performance monitoring is correlated to particular data patterns to provide an accurate determination of variations or other inconsistencies within the clock recovery module.

Abstract: A system and method provide for calibrating the frequency response of an electronic filter. The system and method include a radio transmitter with both in-phase and quadrature baseband paths. Each baseband path includes a numerically controlled oscillator (“NCO”), a digital signal path, a digital-to-analog converter (“DAC”), and an analog filter. A low frequency tone is applied from the NCO from one of the baseband path, while a high frequency tone is applied from the NCO in the other baseband path. An analog peak detector at output determines which analog filter has the largest amplitude at the output. The peak detector offset between the two analog filters is offset by stimulating the in-phase and quadrature baseband paths with the respective NCOs to find an amplitude difference between the output signals from the NCOs that makes the output of the analog filters the same.

Abstract: In one embodiment, a loss-of-signal detector is provided that is immune to variations in common mode voltage for a received differential input signal. The loss-of-signal detector is configured is to use a reference voltage that depends upon the common mode voltage.

Abstract: The present invention generally relates to a method and apparatus for effectively detecting and characterizing noise and other events affecting a communications system such as DSL. According to certain aspects, the invention includes a noise analysis engine that is embedded in customer premises equipment that classifies noise sources according to their specific characteristics and tracks each noise source in a dynamic manner, in such a way as to provide visibility to the changing noise environment within the customer premises and/or report this environment to a remote entity.

Abstract: A method and apparatus to reduce the level of quantification noise when transmission power varies with frequency. Power variation is carried out in the analog domain by filtering a frequency band and attenuating a complementary band in two signal analog-processing paths. More precisely, the method for reducing the quantification noise for transmitting a multi-carrier signal comprises an IFFT conversion step, a digital-to-analog conversion step and an analog-processing step of the signal frequencies on a band having a maximal frequency. Moreover, the analog processing step includes at least two processing paths in parallel to the analog signal, in which: for at least one first path, the signal is filtered so as to retain only the frequencies of a low-frequency band and, in parallel in at least one second path, the signal is subjected to gain, amplification or gain attenuation and, in a final step, the signals from the paths are summed.

Abstract: An apparatus is disclosed where a Powerline interface is used to transmit data into the powerline grid network, where the powerline interface is pulling the required transmit energy from the power grid network, where the powerline interface is transmitting data using standard narrow band modulation such as ASK, FSK, S-FSK, where the transmitted data are passed on to the powerline interface by the use of an “Input signal” adapation stage, where an error calculation and a comparison to a “Triangle” signal is performed to create a command signal used to enable the transmission of data by providing enough voltage to polarize the Transistor (i.e: MOS FET) used in the powerline path.

Abstract: Systems and methods for measuring transmitter and/or receiver I/Q impairments are disclosed, including iterative methods for measuring transmitter I/Q impairments using shared local oscillators, iterative methods for measuring transmitter I/Q impairments using intentionally-offset local oscillators, and methods for measuring receiver I/Q impairments. Also disclosed are methods for computing I/Q impairments from a sampled complex signal, methods for computing DC properties of a signal path between the transmitter and receiver, and methods for transforming I/Q impairments through a linear system.

Abstract: A method for time delay estimation performed by a physical computing system includes passing a first input signal obtained by a first sensor through a filter bank to form a first set of sub-band output signals, passing a second input signal obtained by a second sensor through the filter bank to form a second set of sub-band output signals, the second sensor placed a distance from the first sensor, computing cross-correlation data between the first set of sub-band output signals and the second set of sub-band output signals, and applying a time delay determination function to the cross-correlation to determine a time delay estimation.

Abstract: The present invention relates to data processing techniques in multi-channel data transmission systems. In this invention, a novel approach is proposed to deal with FEXT interferences in the application of high/ultra-high speed Ethernet systems. Compared with the traditional FEXT cancellation approaches, the proposed FEXT canceller can deal with the non-causal part of FEXT, and thus can achieve better cancellation performance. Instead of using the conventional DFE, structure, TH precoding technique is incorporated into the proposed design to alleviate the error propagation problem. The resulting FEXT cancellers do not contain feedback loops which makes the high speed VLSI implementation easy. A modified design is also developed by using a finite signal as the input to the FEXT canceller such that the hardware complexity of the proposed FEXT canceller can be reduced.

Abstract: A communication medium determining apparatus determines a communication medium in use for communication between two devices on a network. The apparatus includes a communication performance obtaining unit which obtains values indicating transmission speeds in a given communication path when a device which decreases transmission speed in a specific communication medium when activated, is active and when the device is inactive. The apparatus further includes a communication medium determining unit which determines whether or not the communication through the given communication path is performed using the specific communication medium. This determination is based on a speed decrease value indicating a decrease amount of the transmission speed in the specific communication medium caused by activation of the device, and a speed difference value which is a difference in the transmission speed obtained by the communication performance obtaining unit between when the device is active and when the device is inactive.

Abstract: A test circuit may include an analog signal generator having an output and configured to generate an analog output signal at the output in accordance with a timing parameter; an analog-to-digital converter (ADC) having an input connected to the output of the analog signal generator, and an output and configured to generate a first digital output signal dependent on the analog signal; and a configurable digital signal generator comprising an output and configured to generate a second digital output signal in accordance with the timing parameter at the output.

Abstract: A method and apparatus are provided for calculating s-parameters of a device under test from step waveforms acquired by a time domain network analyzer.

Abstract: Systems, processes, and structures allow enhanced near-field testing of the uplink and/or downlink performance of MIMO wireless devices (DUT), such as for any of product development, product verification, and/or production testing. Signal channels may preferably be emulated to test the performance of a device under test (DUT) over a range of simulated distances, within a near-field test environment. An enhanced process provides automated testing of a DUT over a wireless network, e.g. such as but not limited to a WLAN. The enhanced MIMO channel emulator may preferably be operated over a high dynamic range.