Abstract: In a method for generating a single data unit for transmission via a communication channel, a preamble and a first portion of a data payload of the single data unit are generated. A midamble is generated, the midamble including at least one OFDM (Orthogonal Frequency Division Multiplexing) symbol that includes calibration information. A second portion of the data payload of the single data unit is generated, and the midamble is included between the first portion of the data payload and the second portion of the data payload.

Abstract: The methods and apparatus described herein are used to operate a wireless device. One method of operating a wireless device includes filtering a first set of digital samples using a first filter at a first time to generate a first signal, transmitting the first signal, filtering a second set of digital samples using a second filter at a second time to generate a second signal, and transmitting the second signal. In one embodiment, an apparatus for operating a wireless device includes a processor configured to filter, at a first wireless device, a first set of digital samples using a first filter at a first time to generate a first signal, transmit, from the first wireless device, the first signal, and filter, at the first wireless device, a second set of digital samples using a second filter at a second time to generate a second signal.

Abstract: A non-linear detector for detecting signals with signal-dependent noise is disclosed. The detector may choose a data sequence that maximizes the conditional probability of detecting the channel data. Since the channel may be time-varying and the precise channel characteristics may be unknown, the detector may adapt one or more branch metric parameters before sending the parameters to a loading block. In the loading block, the branch metric parameters may be normalized and part of the branch metric may be pre-computed to reduce the complexity of the detector. The loading block may then provide the branch metric parameters and any pre-computation to the detector. The detector may then calculate the branch metric associated with the input signal and output the channel data.

Abstract: A method includes filtering a received signal to generate a band-pass filtered signal using a band-pass filter having a pass-band including frequencies located within a central lobe of a power spectrum associated with a target channel of a plurality of channels supported by a communications system. The pass-band is approximately centered at a frequency of a null of a power spectrum associated with at least one other channel of the plurality of channels supported by the communications system. The method includes processing the received signal based on the band-pass filtered signal. The at least one other channel may include at least one of an alternate channel and an adjacent channel of the plurality of channels.

Abstract: Disclosed are various embodiments providing adaptive path selection for interference cancellation for wireless communication devices. Signal strength metrics are obtained for each of multiple signal paths. One or more of the signal paths are selected as cancellation candidates in response to determining that the signal paths are associated with a strong interfering path based at least in part on the signal strength metrics for the signal paths and threshold criteria. Cancellation is enabled for an estimated signal generated using the signal paths in response to the signal paths being selected as cancellation candidates.

Abstract: A technique for wirelessly transmitting management data without cables in a data center is provided. Management data is obtained at a device in the data center. A wireless management data signal is generated from the management data. The wireless management data signal is configured to be transmitted at frequencies matching an ambient electromagnetic noise emitted by the data center, such that the wireless management data signal is masked in the ambient electromagnetic noise emitted by the data center. The wireless management data signal is wirelessly transmitted to another device.

Abstract: Determining a frequency offset of a received signal utilizing two or more multipath components of the received signal is provided herein. By way of example, the received signal can be correlated with a synchronization sequence in a time domain or a frequency domain, resulting in separation of the two or more multipath components of the received signal. Analysis of at least one of the multipath components can provide a frequency offset of the received signal. Furthermore, by analyzing the multipath components, estimation of the frequency offset can be improved as compared with single-signal analysis techniques.

Abstract: A method for receiving a broadcasting signal and a broadcasting signal receiver are disclosed. Even when a cell is changed while an emergency alert is output, the emergency alert can be continuously output using emergency alert table information included in the broadcasting signal and channel information of the cell. The emergency alert table information may include a cell identifier and the channel information of the cell may include virtual channel information of the cell.

Abstract: Methods are described for near optimal Antenna and/or sensor selection via population-based probabilistic evolutionary algorithms such as estimation of distribution algorithm (EDA) and bio-inspired Optimization (BIO). The aspects of the invention includes a method for joint transmit and receive antenna selection using EDA; and an enhanced EDA, which uses cyclic shift register and biased estimation of distribution; and methods for joint transmit and receive antenna selection using improved population-based optimization. The proposed EDA-based and bio-inspired selection methods results in performances that are close to the ESA (exhaustive search algorithm) and yet impose mush less computational burden than ESA. Another advantage of our methods is that they can be easily implemented on parallel processors.

Abstract: A device is adapted for use in a body area network capable of low power communications wherein a number of piconets can operate within close proximity. The device is configured to couple to a plurality of secondary devices in a piconet. The device uses an interference mitigation technique to enable the devices in the piconet to use the same frequency and same time as a number of adjacent piconets located in close proximity to the piconet. The interference mitigation technique is at least one of a low duty cycling operation; and a preamble sequence designed to operate under interference.

Abstract: A receiver suppresses noise simultaneously using a noise suppressor and an automatic gain controller (AGC). The receiver divides a received signal into an audio period and a non-audio period, analyzes whether the noise characteristic of the non-audio period corresponds to a non-static noise or a static noise, and if the noise characteristic corresponds to the static noise, analyzes whether the static noise is caused by a network or a transmitter side terminal. In accordance with the analyzed noise characteristic, the noise suppressor firstly suppresses the noise by determining the noise suppressing intensity, and sends a signal, from which the noise has been firstly suppressed, to the AGC. The AGC secondly suppresses the noise included in the signal. In this case, the threshold value of the AGC is controlled in real time in accordance with the noise characteristic.

Abstract: The present invention provides a channel estimation apparatus in which channel estimation may be made higher than heretofore in accuracy and may be used for calculating the weight for an equalization filter to achieve an optimum equalizing performance. A subcarrier copying unit 20 copies K items of end-side subcarriers, using the channel estimation obtained by a correlation processing unit 14 and K which is a subcarrier copy number. An IDFT unit 15 transforms the channel estimation obtained at the subcarrier copying unit 20 into the time domain channel response. A noise path removing unit 16 removes noise paths from the channel response output from the IDFT unit 15. A DFT unit 17 performs DFT of the channel response, from which the noise paths are removed by the noise path removing unit 16, to output a noise-suppressed frequency domain channel estimation value. A weight calculation unit 5 inputs the frequency domain channel estimation value output from the DFT unit 17 to calculate an equalizing weight.

Abstract: The method is for managing operation of a first apparatus belonging to a first communication system and exchanging within the first communication system a multi-carrier modulated signal on several sub-carriers. The method includes detecting at the first apparatus the presence of an interfering signal emitted from a victim apparatus on a sub-carrier. The method may also include determining at the first apparatus the path loss between both apparatuses, determining from the path loss and from an allowed interference level at the victim apparatus a maximum allowed transmit power on the sub-carrier of a multi-carrier modulated signal to be transmitted from the first apparatus, and adjusting within the first apparatus the processing of the multi-carrier modulated signal to be transmitted in accordance with the maximum allowed transmit power.

Abstract: Interference cognitive devices are described. An interference cognitive device can be collocated with a transmitter of an interference cognitive transmitter (ICT), as receive chains or portions thereof at the ICT. An interference cognitive device can also be remote with respect to the transmitter, which operates in an interference cognitive network and receives data directly or indirectly from the interference cognitive device. The ICT uses the data to mitigate interference while continuing to operate in accordance with a performance metric.

Abstract: A channel estimation method, comprising when it is determined that in-band SRSs are required to be transmitted, acquiring the number of transmitting antenna ports and the number of layers of the currently transmitted DMRSs; calculating the difference of the number of the transmitting antenna ports and the number of layers of the currently transmitted DMRSs, and using the difference as the number of in-band SRSs that are required to be transmitted; transmitting in-band SRSs to a receiving-end device according to the number of in-band SRSs that are required to be transmitted, to enable the receiving-end device to perform channel estimation according to the currently transmitted DMRSs and the received in-band SRSs.

Abstract: The present invention discloses a method, device and system for configuring codebooks. The method comprises a transmitting end selecting a code word restricted sub-set and informing a receiving end of the code word restricted sub-set, the code word restricted sub-set containing part or all of code words in a first codebook and/or a second codebook; and the receiving end selecting an optimal pre-coded code word from the code word restricted sub-set and informing the transmitting end of an index of the optimal pre-coded code word. By the present invention, code word restriction is implemented in the case of dual codebooks in the LTE-A system such that the calculation complexity is reduced when the receiving end selects the code word, occurrences of the case where the receiving end selects the code word wrongly are decreased, and the signaling structure in the LTE system can be inherited very well.

Abstract: A transmitter is for use with multiple transmit antennas and includes a precoder unit configured to precode data for a transmission using a precoding matrix selected from a codebook, wherein the codebook corresponds to the following three transmission properties for an uplink transmission: 1) all precoding elements from the precoding matrix have a same magnitude, 2) each precoding element from the precoding matrix is taken from a set of finite values and 3) there is only one non-zero element in any row of the precoding matrix. The transmitter also includes a transmit unit configured to transmit the precoded data.

Abstract: Various schemes for reducing effects of interference within communication systems are disclosed. A transmitter transmits a signal in a first time interval and a scrambled version of the signal in a second time interval, which does not overlap with the first time interval. A receiver receives a composite signal including a signal transmitted from the desired transmitter as well as signals from interferers in the first or the second time interval. The receiver determines a dominant interferer and obtains knowledge of signal scrambling done by the interferer as well as the desired transmitter by sensing an identification associated with the interferer or the desired transmitter. This knowledge is employed to determine coefficients for combining the received composite signals received in the first and the second time interval in order to recover the desired signal in a manner that maximizes the SNR associated with the desired signal or completely cancels the dominant interference.

Abstract: According to one embodiment, a semiconductor integrated device includes a digitally controlled oscillator, a counter, a time to digital converter, an adder, and a control signal generator. The time to digital converter includes a frequency-divider, a plurality of impedance elements, and a phase difference detector. The frequency-divider is configured to frequency-divide the oscillation signal to generate a plurality of frequency-divided signals. The plurality of impedance elements is configured to voltage-divide the frequency-divided signals to generate a plurality of delay signals of the oscillation signal. The phase difference detector is configured to output the third digital signal corresponding to the phase difference between the reference signal and the oscillation signal by comparing the reference signal with each of the delay signals.

Abstract: Various systems and methods providing high speed decoding, enhanced power reduction and clock domain partitioning for a multi-pair gigabit Ethernet transceiver are disclosed. ISI compensation is partitioned into two stages; a first stage compensates ISI components induced by characteristics of a transmitter's partial response pulse shaping filter in a demodulator, a second stage compensates ISI components induced by characteristics of a multi-pair transmission channel in a Viterbi decoder. High speed decoding is accomplished by reducing the DFE depth by providing an input signal from a multiple decision feedback equalizer to the Viterbi based on a tail value and a subset of coefficient values received from a unit depth decision-feedback equalizer. Power reduction is accomplished by adaptively truncating active taps in the NEXT, FEXT and echo cancellation filters, or by disabling decoder circuitry portions, as channel response characteristics allow.

Abstract: Systems and methods for interference cancellation at a receiver in a wireless communication system are provided. In one aspect, a method for interference cancellation is provided. The method comprises providing total received chips received from a plurality of cells. The method also comprises successively estimating received chips for each of the plurality of cells in a plurality of iterations, wherein each of the plurality of iterations after a first iteration comprises canceling previously estimated received chips for one or more of the plurality of cells from the total received chips, and estimating received chips for one of the plurality of cells using the total received chips with the previously estimated received chips for the one or more of the plurality of cells cancelled out.

Abstract: A data modulation method, a data demodulation method, and a method, include obtaining a target frequency band allocated to a transmitting terminal; calculating a precoding codeword index of spectrum shaping according to a codebook corresponding to a current radio scene and the target frequency band, where the codeword index corresponds to a return-to-zero subcarrier sequence, and the return-to-zero subcarrier sequence serves to calculate a precoding vector for modulating data; and sending the precoding codeword index out through broadcast.

Abstract: A receiver and a transmitter that copes with interference in a super-regenerative communication system, and a method of using the receiver and the transmitter, are provided. A super-regenerative receiver includes a resonance frequency adjusting unit configured to adjust a resonance frequency associated with a filtering band of a transmission signal that is received from a transmitter. The super-regenerative receiver further includes an oscillation signal generating unit configured to generate an oscillation signal, using a positive feedback amplification, based on the resonance frequency and the transmission signal. The super-regenerative receiver further includes an oscillation characteristic detecting unit configured to detect a characteristic of the oscillation signal. The super-regenerative receiver further includes a determining unit configured to determine whether interference is included in the transmission signal based on the characteristic of the oscillation signal and the resonance frequency.

Abstract: A receiver that easily receives signals from transmission channels having long cable lengths is presented. The receiver includes an analog pre-filter that removes distortions and intersymbol interference from a predetermined transmission channel. The analog pre-filter is coupled with a digital receiver that provides digital equalization. The combination of analog equalization with digital equalization allows for simplified digital equalization while retaining the versatility of digital signal processing.

Abstract: A receive signal processor jointly detects two or more symbols in a signal-of-interest in the presence of one or more other MIMO signals. The signal-to-interference-plus-noise ratio for each signal-of-interest is determined by computing per-subcarrier signal-to-interference-plus-noise ratios for a plurality of subcarriers allocated to the signals-of-interest, and computing a total signal-to-interference-plus-noise ratio for the subcarriers based on the per-subcarrier signal-to-interference-plus-noise ratios of the subcarriers. A controller determines one or more transmission formats for uplink transmissions based on the signal-to-interference-plus-noise ratios. The process of computing per-subcarrier signal-to-interference-plus-noise ratio reflects the amount of MIMO interference already cancelled or still remaining in the signal arriving at the joint detector.

Abstract: A technique for processing received signals in multiple-antenna systems. Received signals from the different antennas may be amplified by a Low Noise Amplifier (LNA) and time-multiplexed by a switch to form a single analog signal. The time-multiplexed analog signal is down-converted and processed using a single RF chain for each signal component. This may result in an N-fold decrease in hardware in multiple antenna receiver systems.

Abstract: Disclosed is a co-channel feedback signal cancelling regenerative repeater of the Advanced Television Systems Committee (ATSC) that extracts a predetermined reference value of feedback signal to be able to cancel the feedback signal among received signals, including: a signal receiving unit; a signal demodulating unit that converts frequency of a received signal and demodulates it into a baseband signal; an interference equalizing unit that corrects characteristics of the demodulated signal and cancels feedback signal; a channel equalizing unit that compensates for channel distortion of an original signal from which the feedback signal is cancelled; a modulating unit that modulates the channel distortion-compensated original signal and converts it into an analog signal; and a signal transmitting unit that converts the frequency of the modulated signal, controls and amplifies its gain, and transmits a regenerative transmission signal.

Abstract: A system and method for realizing distributed interference alignment is disclosed. The system comprises a retrieving module, a determination module and a precoding module. The retrieving module retrieves source data. The determination module generates data describing one or more requirements for one or more associated Interference Alignment (IA) groups. The precoding module calculates a precoding vector based at least in part on the data describing the one or more requirements for the one or more associated IA groups. The precoding module is communicatively coupled to the retrieving module to receive the source data. The precoding module generates a transmission signal based at least in part on the precoding vector and the source data.

Abstract: In the present disclosure, several techniques are proposed to estimate the worst-case crosstalk noise and use it for bit-loading and SRA calculations so that fluctuating crosstalk when PET mode is enabled does not lead to system instability. One of the proposed techniques involves strategically placing some marker tones in the transmitters of the affecting lines. The noise floor may be inferred by interpolating the noise observed on these marker tones (tones that are always-on) and applying to the entire frequency band on the victim line. Another proposed technique involves periodically transmitting a set of marker symbols (fully loaded OFDM symbols), so that a victim channel can estimate the SNRs in a worst case crosstalk scenario.

Abstract: A broadband device (105) can detect a proximate narrowband transmission (152) from a narrowband communication device (145). The narrowband transmission (152) can be in close enough proximity (155) to at least one bearer channel of the broadband device (105) to result in interference on the narrowband reception (152) when the broadband device (105) is transmitting and the narrowband communication device (145) is concurrently receiving. Responsive to the detecting, the broadband device (105) can gate a broadband transmission (142) to ensure the broadband transmission (142) does not interfere with the proximate narrowband reception (152). In absence of detecting the narrowband transmission (152), the broadband transmission (142) from the broadband device (105) would not be gated.

Abstract: A first device receives a first signal transmitted over a transmission line from a second device. The first signal is processed and information is generated that is related to crosstalk from other transmission lines. The information is modulated onto at least one carrier of a plurality of carriers of a second signal to be transmitted from the first device to the second device.

Abstract: Example embodiments include methods of interference cancellation at NodeB receivers of baseband antenna signals including physical channels. The methods include canceling interference from a received baseband antenna signal by removing a reconstructed baseband signal from the processed received baseband antenna signal. The processed reconstructed baseband signal includes users whose physical data channel signals were successfully decoded. Methods also include removing interference from a received baseband signal to form an interference cancelled baseband signal that will be processed by the receiver. The interference cancelled baseband signal is the received baseband antenna signal minus users' signal interference contributions whose demodulated physical data channel signals have a determined user symbol energy value that exceeds a threshold. Methods further include removing interference from a user's signal to be error corrected.

Abstract: A method includes accepting input values u and v, respectively identifying a uth root Zadoff-Chu sequence whose length is a prime number, and a vth cyclic shift for the sequence. Elements of a Discrete Fourier Transform (DFT) of the vth cyclic shift of the uth root Zadoff-Chu sequence are computed using processing circuitry, by evaluating a single respective exponent depending on u and v in computing each of the elements.

Abstract: A transceiver circuit is disclosed. The transceiver circuit comprises a receive path to receive a differential signal and a first crosstalk filter coupled to the receive path. A common-mode path is provided for carrying a common-mode signal. An RFI interference filter is coupled between the common-mode path and the receive path. Isolation circuitry decouples the RFI interference filter from the first crosstalk filter.

Abstract: A multistage channel estimation method and apparatus is provided. The multistage channel estimation method includes: receiving a data frame to compensate for a distortion of the data frame based on a first channel estimation value associated with a corresponding section of the data frame; a first step of changing the corresponding section to calculate a second channel estimation value associated with the changed section; a second step of updating the first channel estimation value based on the calculated second channel estimation value; a third step of compensating for the distortion of the data frame based on the updated first channel estimation value to count a number of compensations; and repeating the first step through the third step, when the counted number of compensations does not match a predetermined numerical value.

Abstract: A local carrier wave output from a synthesizer to quadrature demodulators is multiplied by an offset that makes a frequency shift by an integer number of subcarriers in units of sub-carrier bands. The offset is set to a value obtained by multiplying the number sequentially counted up from 0 to the number of unused sub-carriers included in guard tones in a signal band by the bandwidth of a sub-carrier. By shifting the frequency of the local carrier wave at the time of quadrature demodulation with the offset, the SNR of a baseband signal is prevented from being constantly degraded by a frequency characteristic possessed by the circuit of a receiver in a particular sub-carrier signal. Especially, by preventing a pilot signal from being constantly degraded, the signal can be received with higher accuracy.

Abstract: Apparatuses and methods for transmitting and receiving in a multi-antenna system are provided. A receiver for reducing a quantization error of channel information feedback in a multi-antenna system includes a restore vector generator for selecting a codeword ck and d determining a real part wkreal and an imaginary part wkimag of a restore vector corresponding to the codeword; and a post-processor for performing post-processing by multiplying the real part wkreal of the restore vector by a first reception signal and multiplying the imaginary part wkimag of the restore vector by a second reception signal.

Abstract: A distortion compensation device includes a storage unit storing a plurality of distortion compensation coefficients associated with power values of transmission signals, a distortion compensation processing unit acquiring a distortion compensation coefficient corresponding to a power value of a received transmission signal from among the plurality of distortion compensation coefficients and subjecting the received transmission signal to a distortion compensation process on the basis of the acquired distortion compensation coefficient, a phase calculating unit calculating a phase correction value on the basis of the distortion compensation coefficients, a phase correcting unit generating a reference signal by correcting a phase of the received transmission signal on the basis of the phase correction value, and a correction processing unit performing a correction process for the transmission signal subjected to the distortion compensation process on the basis of the reference signal and a feedback signal from

Abstract: A system for and method of removing one or more unwanted inband signals from a received communications signal is described. The inband signal or signals may comprise noise, interference signals, or any other unwanted signals that impact the quality of the underlying communications. A receiver receives a communication signal, the received communication signal including the desired communication signal and one or more inband signals. A signal processor processes the received signal to form an estimate of the desired communication signal and an estimate of the inband signals. The estimate of the inband signals is thereby removed from the received signal. The estimate of the desired communication signal and the estimate of the inband signals are formed without prior knowledge of characteristics of the inband signals and without obtaining a copy of any of the inband signals from any source other than the received signal.

Abstract: An orthogonal transform subunit 14 separates a reception signal into carriers on a per-symbol basis.

Abstract: A method for performing device-to-multidevice communication with interference suppression is provided. The method may include selecting at least one receiving user equipment for D2MD transmission, and receiving requested data rates from the selected at least one receiving user equipment. The method may further include acquiring CSI matrices and identifying interference constraints to the C-UEs sharing the same frequency band as the at least one receiving user equipment. The method then includes determining precoding matrices using the acquired CSI matrices and the identified interference constraints to the C-UEs, and performing D2MD transmission to the at least one receiving user equipment using the determined precoding matrices.

Abstract: The present invention provides a data stream processing method, device, and system. The data stream processing method includes: using a precoding parameter to perform precoding processing on an lth to-be-sent data stream of a current kth transmitting device, where the lth to-be-sent data stream includes a lattice point data stream mapped to a lattice grid; and sending the precoded lth to-be-sent data stream to a kth receiving device, where both l and k are positive integers. The technical solutions in the embodiments of the present invention can be helpful for filtering out interference, exactly complies with an actual processing procedure of an interfering data stream, and have strong practicability.

Abstract: A method for transmitting data between a radio transmitting device and a radio receiving device includes transmitting a frame structure over a radio channel, the frame structure including a control channel and a data channel. The method further includes detecting a quality degradation of the radio channel, selecting a bit from the data channel and increasing a transmission power of the selected bit when the quality degradation of the radio channel is detected.

Abstract: Embodiments herein disclose an Interference Cancelling Block Modulation (ICBM), a new open-loop precoding scheme where each transmitter is assigned with a predetermined precoder which facilitates interference cancellation at the receivers. Only a finite set of precoders will be used, and they will be assigned to each transmitter in a pre-determined manner. Usually, interfering transmitters located adjacent to each other will have different precoders, and the same precoder can be reused by non-adjacent transmitters. The precoders are represented by N×K matrices and they expand the symbols in time and/or frequency by a factor of N/K while providing precoded sequences with low cross-correlation properties.

Abstract: DFT-based channel estimation methods and systems are disclosed. One system includes an inverse discrete Fourier transform module, a noise power estimator, a noise filter and a discrete Fourier transform module. The inverse discrete Fourier transform module is configured to determine time domain estimates by applying an inverse discrete Fourier transform to initial channel estimates computed from pilot signals. Additionally, the noise power estimator is configured to estimate noise power by determining and utilizing time domain samples that are within a vicinity of sinc nulls of the time domain estimates. The noise filter is configured to filter noise from the time domain estimates based on the estimated noise power to obtain noise filtered time domain estimates. Further, the discrete Fourier transform module is configured to perform a discrete Fourier transform on the noise filtered time domain estimates to obtain frequency domain channel estimates for channels on which pilot signals are transmitted.

Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for selecting receiver gain adjustment values. In one aspect, a method includes receiving aggregate signal characteristic values (“aggregate values”) for a plurality of signals being received over active channels of a power line communications network, the aggregate values being computed based on signal characteristic values for each of the signals being received over the active channels. Using the aggregate values, a determination is made that one or more of the aggregate values have been outside of a valid range of signal characteristic values over a specified period. In response to determining that the aggregate values have been outside of the valid range, a receiver gain adjustment value is selected based on the aggregate values and a receiver gain of a receiver that receives the signals is adjusted.

Abstract: A method and a radio base station for interleaving control channel data to be transmitted in a telecommunications system are described. The method comprises grouping the control channel elements CCE1-CCEn into a first order of control channel symbol groups, determining a number of available symbol group positions of control channel transmission resources, adding symbol groups comprising “dummy” values or zeros to the first order of control channel symbol groups, interleaving the first order of the control channel symbol groups resulting in an a second order, cyclic shifting the second order and mapping the cyclic shifted second order of control channel symbol groups to the control channel transmission resources.

Abstract: Large interfering signals (interferers) with spectra near a desired signal can cause distortion in a wireless receiver due to a non-linear signal path. It is typically a performance advantage to attenuate these interferers earlier in the signal path, rather than later in the signal path, because these interferers can cause saturation of amplifying stages. In certain situations, the frequency offset of an interfering signal, with respect to the desired signal, can be on the order of 10 megahertz (MHz), whereas the center frequencies can be on the order of several gigahertz (GHz). Thus, a filter with “baseband” precision would be needed at radio frequency to notch out the interferer, which is relatively difficult to do. Disclosed is a technique to estimate the relative strength and center frequency of the interferer and to place the center frequency of a notch filter adaptively and precisely at the interferer location.

Abstract: Embodiments of the present invention provide an apparatus and method for crest factor reduction, in which an input time domain signal is clipped to generate a clipped signal and a difference signal, and processing operations are carried out on the difference signal, before the processed difference signal is combined with the clipped signal to generate an output time domain signal.

Abstract: The present invention provides an interference removal method in a multi-node system. The interference removal method comprises receiving node information from a base station; receiving a first signal from an objective node and a second signal from an interference node; and removing interference due to the second signal by applying a receive filter to a receive signal including the first and the second signal, where the node information includes at least one of information about a reference signal included in the second signal and information about a pre-coding matrix applied to the second signal and the receive filter is determined based on the node information.