1053results about "Modulation type identification" patented technology

A method and apparatus for conducting a pilot signal search in a wireless communications network. The location of a mobile is determined within the network. This location is then used in determining search window sizes and other search parameter information that is used to search all pilot signals identified in a designated pilot signal set. Search window size is also determined based upon the location of the mobile and another component related to multipath effects for a transmitted pilot signal.

Embodiments are directed to transmitting L1 pre-signaling information with predetermined modulation and code rate such that L1 pre-signaling information can be received without preliminary knowledge on the network. L1 pre-signaling information makes it possible to receive the L1 signaling information, data link layer information, and notification data that may have configurable code rates and modulation. Therefore, L1 pre-signaling information can be thought of as signaling metadata (i.e., information about other signaling information). L1 signaling is divided into pre-signaling and signaling parts. The pre-signaling part includes parameters used for receiving the L1 signaling information. L1 pre-signaling signaling enables the receiver to receive the signaling itself (L1 signaling and data link layer information) by informing the receiver about the type of modulation, coding, and the like, used to transmit the L1 signaling, data link layer, and notification information.

A method and apparatus for efficiently selecting a demodulation scheme for a particular channel in a digital broadcast receiver supporting a plurality of demodulation schemes are provided. The method includes receiving the digital broadcast signal of the channel; attempting demodulation of the digital broadcast signal using a demodulation scheme corresponding to a sequential index; and if the demodulation attempt succeeds, restoring data and if the demodulation attempt does not succeed, attempting demodulation again using a demodulation scheme corresponding to a next sequential index.

A method of identifying a signal type uses parameters of the signal as a basis for automatic identification. A signal of interest is selected from a display of a spectral waveform for a specified frequency. An occupied bandwidth for the signal of interest is estimated and, if the occupied bandwidth is common to more than one known signal type, a complementary cumulative distribution function of peak power for the signal of interest is estimated. The signal type may be identified as a function of these parameters. Additionally the frequency of the signal of interest may be compared with a database of spectral assignments for known signal types to provide further information about the signal of interest.

A receiver for mobile communication includes a wireless scheme parameter storing unit (23) configured to store a plurality of characteristics of multiple wireless schemes, a wireless scheme estimation unit (22) configured to estimate one of the characteristics of a currently used wireless scheme from a received signal and select one of the wireless schemes corresponding to the estimated characteristic from the wireless scheme parameter storing unit, and a demodulator (24) configured to demodulate the received signal based on the selected wireless scheme.

An apparatus and method for signal detection in a CR-based wireless communication system are provided. In the signal detection apparatus, a cyclic power calculator calculates the power spectral density of a cyclo-stationary and periodical signal to be detected with respect to a cyclic frequency and calculates optimum statistics using the power spectral density. A signal detector determines whether a signal exists or not according to the optimum statistics.

A method, radio receiver, and system to autonomously receive and decode a plurality of signals having a variety of signal types without a priori knowledge of the defining characteristics of the signals is disclosed. The radio receiver is capable of receiving a signal of an unknown signal type and, by estimating one or more defining characteristics of the signal, determine the type of signal. The estimated defining characteristic(s) is / are utilized to enable the receiver to determine other defining characteristics. This in turn, enables the receiver, through multiple iterations, to make a maximum-likelihood (ML) estimate for each of the defining characteristics. After the type of signal is determined by its defining characteristics, the receiver selects an appropriate decoder from a plurality of decoders to decode the signal.

A method for automatically detecting a packet mode in a wireless communication system supporting a multiple transmission mode includes: acquiring at least one of data rate information, packet length information and channel bandwidth information from a transmitted frame; and determining the packet mode on the basis of the phase rotation check result of a symbol transmitted after a signal field signal and at least one of the data rate information, the packet length information and the channel bandwidth information acquired from the transmitted frame.

A method implemented by a Wireless Transmit / Receive Unit (WTRU) includes receiving a DeModulation Interference Measurement (DM-IM) resource, determining an interference measurement based on the DM-IM resource, and demodulating a received signal based on the interference measurement. An interference is suppressed based on the interference measurement. At least one DM-IM resource is located in a Physical Resource Block (PRB). The DM-IM resource is located in a PRB allocated for the WTRU. The DM-IM resource is a plurality of DM-IM resources which form a DM-IM pattern, and the DM-IM pattern is located on a Physical Downlink Shared Channel (PDSCH) and / or an enhanced Physical Downlink Shared Channel (E-PDSCH) of at least one Long Term Evolution (LTE) subframe. The DM-IM resources are different for different Physical Resource Blocks (PRB) in the LTE subframe. The DM-IM is located in a Long Term Evolution (LTE) Resource Block (RB), and the DM-IM pattern is adjusted.

The present invention provides a unique feedback system in a wireless communication system wherein the transmission channel is always overloaded with data, which is configured and modulated at a select order of modulation. Based on the channel conditions, only a portion of the data can be successfully received. As such, the receiver will attempt to receive the data using demodulation techniques corresponding to the different levels of modulation used to encode the data transmitted. The receiver will determine the data that is recovered, or the highest order of modulation at which the data is recovered, and provide feedback to the transmitter. The transmitter will then retransmit the data that was not properly received. By overloading the channel at all times, the maximum amount of data capable of being transmitted over the channel is optimized without requiring or heavily relying on the receiver feeding back channel condition information to the transmitter.

A subchannel scheduling method in a multi-user MIMO-OFDM environment modifies proportional fairness scheduling specifications and maximizes a system throughput under conditions that a minimum data transmission rate required by a multimedia user be ensured. In a method for allocating subchannels in a wireless network, plural users are subscribed in the wireless network, a base station has NT transmission antennas, a user i has NR reception antennas, a network capacity determined by the NT transmission antennas and K subcarrier groups is divided into K transmission subchannel groups, and a network bandwidth determined by the NT transmission antennas is divided into the K subchannel groups. The base station sequentially allocates channels to the users on the basis of a proportional value of a data transmission rate supported to each user and an average throughput of each user in a predetermined time and a service quality required by each user.

The invention discloses a modulation mode identification system and method based on a convolutional neural network, which solve the problems of complex feature extraction steps and low identificationrate under a low signal-to-noise ratio in the prior art. The simple feature in the identification system is constructed as a simple feature using a co-directional component and a quadrature componentof a baseband signal as signals, and the simple feature is sent to a convolutional neural network module for identification. The identification method comprises the steps of: modulating a transmittedsignal and performing pulse shaping; performing up-conversion on the transmitted signal and then transmitting the transmitted signal through an additive white Gaussian noise channel; performing pre-processing first by a receiving end to obtain the co-directional component r(t) of the analyzed signal; constructing the simple feature, i.e., constructing the co-directional component r(t) and the quadrature component of the analyzed signal into a two-dimensional matrix; performing feature learning and classification by the convolutional neural network; and sending a modulation method to a demodulation end to obtain a demodulated signal. The method is low in feature design complexity, avoids explicit feature extraction, has high classification correctness, and can be applied to communication systems having high recognition performance requirements.

The present invention is a computationally-efficient compensator for removing nonlinear distortion. The compensator operates in a digital post-compensation configuration for linearization of devices or systems such as analog-to-digital converters and RF receiver electronics. The compensator also operates in a digital pre-compensation configuration for linearization of devices or systems such as digital-to-analog converters, RF power amplifiers, and RF transmitter electronics. The compensator effectively removes nonlinear distortion in these systems in a computationally efficient hardware or software implementation by using one or more factored multi-rate Volterra filters. Volterra filters are efficiently factored into parallel FIR filters and only the filters with energy above a prescribed threshold are actually implemented, which significantly reduces the complexity while still providing accurate results. For extremely wideband applications, the multi-rate Volterra filters are implemented in a demultiplexed polyphase configuration which performs the filtering in parallel at a significantly reduced data rate. The compensator is calibrated with an algorithm that iteratively subtracts an error signal to converge to an effective compensation signal. The algorithm is repeated for a multiplicity of calibration signals, and the results are used with harmonic probing to accurately estimate the Volterra filter kernels. The compensator improves linearization processing performance while significantly reducing the computational complexity compared to a traditional nonlinear compensator.

Apparatus and methods for identifying a wireless signal-emitting device are disclosed. The apparatus is configured to sense and measure wireless communication signals from signal-emitting devices in a spectrum. The apparatus is operable to automatically detect a signal of interest from the wireless signal-emitting device and create a signal profile of the signal of interest; compare the signal profile with stored device signal profiles for identification of the wireless signal-emitting device; and calculate signal degradation data for the signal of interest based on information associated with the signal of interest in a static database including noise figure parameters of a wireless signal-emitting device outputting the signal of interest. The signal profile of the signal of interest, profile comparison result, and signal degradation data are stored in the apparatus.

A system for scanning a frequency spectrum to detect usage thereof includes an ultra-wideband receiver for performing the scanning, and cooperates with a spectrum usage estimator module and a radio controller unit. The spectrum usage estimator module derives from the scanning performed via the ultra-wideband receiver information as to usage of individual bands in the frequency spectrum. The radio controller unit controls operation of a radio cognitive system as a function of the information as to usage of individual bands in the frequency spectrum as derived by the spectrum usage estimator module. The radio cognitive system operates over unused bands in the frequency spectrum.

Methods and apparatuses for acquiring and demodulating a data stream transmitted in a communication system. A method in accordance with the present invention comprises finding a boundary of a physical layer frame (PLFrame) in the data stream, finding a first 26 bits of a Unique Word (UW) associated with the data stream, finding a scrambling code utilizing the UW, and using a decoding procedure to determine a modulation type and code rate used for desired signals within the data stream.

The determination of the signal modulation format for a channel is an important aspect of the operation of a signal receiver. A method (700) is described including the steps of receiving (710) a signal, comparing (720) a sample of the received signal to a first threshold value and a second threshold value, creating (720) a signal profile based on the comparison, and selecting (750) a modulation format for the received signal based on the signal profile. An apparatus (500) is also described including a ring counter (510) that receives a sample of an input signal, compares the sample to a first threshold value and a second threshold value, and creates a signal profile for the input signal, a signal profiler (550) that compares the signal profile for the input signal to at least two reference profiles, and a detector (560) that determines a modulation format for the input signal based on the comparison in the signal profiler (550).

Ultra wide band communication systems and methods are provided. In one embodiment, an ultra wide band communication system includes a first and a second communication device. A lowest common ultra wide band pulse repetition frequency is determined, and data is transmitted between the communication devices using the lowest common ultra wide band pulse repetition frequency. In another embodiment, a first and second slave transceiver communicate with a master transceiver using a time division multiple access frame, with the master transceiver providing transmission synchronization. This Abstract is provided for the sole purpose of complying with the Abstract requirement rules that allow a reader to quickly ascertain the subject matter of the disclosure contained herein. This Abstract is submitted with the explicit understanding that it will not be used to interpret or to limit the scope or the meaning of the claims.

A system for monitoring conditions within a tire (12) including a sensor assembly (14) including a pressure sensor (36), an accelerometer (34), a temperature sensor (32), and a transmitter (40) to transmit signals indicative of current tire conditions. A remote transmitter (22) for actuating a remote keyless entry system (19) emits a signal to actuate a function of the keyless entry system (19) such as unlocking doors (20) of the motor vehicle (10). A receiver assembly (16) includes an amplitude shift keyed receiver (52) and a frequency shift keyed receiver (58) selectively engagable to receive radio frequency transmissions from the tire monitoring system or the remote keyless entry system (19).

The present invention provides a high-performance adaptive digital receiver with adaptive background control that optimizes the performance in rapidly changing signal environments and provides 3.6 GH; instantaneous bandwidth, SFDR>90 dB, SNR=66 dB, with dynamic digital channelization. The receiver takes advantage of several levels of adaptivity that conventional approaches do not offer. In addition to a dynamic digital channelizer that is adaptively tuned based on detected signals, the present invention employs a powerful software reconfigurable digitizer that is adaptively optimized for the current signal environment to control important receiver parameters such as bandwidth, dynamic range, resolution, and sensitivity.

Systems, methods, and apparatuses are provided for fine-sensing modules that are operative for identifying one or more signal types from an input radio frequency (RF) signal. The fine-sensing modules may include a multiplier that combines an RF input signal and a delayed RF input signal to produce a correlation signal and an integrator that receives the correlation signal from the multiplier, where the integrator determines correlation values from integrating the correlation signal. The fine-sensing module also includes a comparator in communication with the integrator that compares the correlation values to one or more thresholds to generate information indicative of at least one signal feature of the RF input signal.

An apparatus of processing a time domain synchronous orthogonal frequency-division-multiplexing (TDS-OFDM) signal is provided. The apparatus includes a receiving block and a demodulating block. The receiving block receives the TDS-OFDM signal, and generates a down-converted signal according to the received TDS-OFDM signal. The demodulating block is coupled to the receiving block, and demodulates the down-converted signal to generate a transport stream. The demodulating block has a transmission parameter signaling (TPS) decoder implemented for performing a TPS decoding operation to generate a TPS decoding result and verifying a spectrum direction of the received TDS-OFDM signal according to the TPS decoding result.

A cellular communications system that utilizes OFDM in its radio interface is capable of utilizing either a first subcarrier spacing or a second subcarrier spacing. Which of these is presently in use is indicated by generating a first type of synchronization signal in response to the first subcarrier spacing presently being in use, and generating a second type of synchronization signal in response to the second subcarrier spacing presently being in use. Whichever of the first type of synchronization signal and the second type of synchronization signal was generated is transmitted. To distinguish between the first and second types of synchronization signals, a time domain representation of the second type of synchronization signal includes a plurality of instances of the first type of synchronization signal.

Provided is a method of estimating a symbol. The method may include deriving phase components of input data, applying a second order differentiation to the phase components to obtain a second order differential phase vector, and estimating symbols corresponding to the input data using the second order differential phase vector.

A method for providing interference suppression in a communication device includes receiving a signal, determining if the received signal comprises a Gaussian Minimum Shift Keying (GMSK) or an 8 phase shift keying (8PSK) signal. Over sampling and inphase and quadrature phase separation with real-valued signal processing on the received signal is performed whenever the received signal is determined to be a GMSK signal. Oversampling with complex-valued signal processing on the received signal is performed whenever the received signal is determined to be an 8PSK signal. A receiver is also disclosed that provides for interference suppression.

A digital broadcasting system and a data processing method are disclosed. The receiving system of the digital broadcasting system includes a baseband processor, a first handler, a second handler, and a storage unit. The baseband processor receives a broadcast signal including mobile service data and main service data. Herein, the mobile service data may configure an RS frame, and the RS frame may include the mobile service data and first signaling information of a first data type on the mobile service data. The first handler parses the first signaling information received from the RS frame, converts parsed data elements of the first data type to a second data type, and merges multiple identification information of the parsed first data type, thereby generating identification information of the second data type. The second handler receives second signaling information of the second data type on the mobile service data, the second signaling information including at least one fragment, uses the identification information of the second data type included in the first handler to search at least one fragment within the second signaling information, and maps data elements received through the searched fragment with the data elements converted to the second data type.