Abstract: Samples of a light radar (“LIDAR”) return signal are stored in an analog circular buffer following the transmission of a LIDAR pulse. Sampling continues for a fixed period of time or number of samples during a post-trigger sampling period after the occurrence of a trigger signal from a trigger circuit. The trigger circuit indicates the receipt of a return pulse associated with a target object based upon one or more return signal characteristics. Following the post-trigger sampling period, the stored analog samples are sequentially read out and converted to digital sample values. The digital sample values may be analyzed in a digital processor to further confirm the validity of the returned LIDAR pulse, to determine a time of arrival of the LIDAR pulse, and to calculate a distance to the target object. Some versions include multiple circular buffers and capture clocks, enabling the capture of samples from multiple return pulses.

Abstract: Samples of a light radar (“LIDAR”) return signal are stored in an analog circular buffer following the transmission of a LIDAR pulse. Sampling continues for a fixed period of time or number of samples during a post-trigger sampling period after the occurrence of a trigger signal from a trigger circuit. The trigger circuit indicates the receipt of a return pulse associated with a target object based upon one or more return signal characteristics. Following the post-trigger sampling period, the stored analog samples are sequentially read out and converted to digital sample values. The digital sample values may be analyzed in a digital processor to further confirm the validity of the returned LIDAR pulse, to determine a time of arrival of the LIDAR pulse, and to calculate a distance to the target object. Some versions include multiple circular buffers and capture clocks, enabling the capture of samples from multiple return pulses.

Abstract: An apparatus is provided. In the apparatus, an input to index (I2I) module maps a complex input into a real signal. A real data tap delay line is coupled to the I2I module and includes N delay-elements. A complex data tap delay line is configured to receive the complex input and includes M delay elements. A set of K of non-linear function modules is also provided. Each non-linear function module from the set has at least one real input, at least one complex input, and at least one complex output. A configurable connectivity crossbar multiplexer couples K of the N real tap delay line elements to real inputs of the set non-linear functions and couples K of the M complex tap delay line elements to complex inputs of the set non-linear function modules.

Abstract: A circuit for use with an amplification circuit having a predistortion datapath portion, a power amplifier portion and a gain portion. The predistortion datapath portion can output a predistorted signal based on the input signal. The power amplifier portion can output an amplified signal based on the predistorted signal. The gain portion can output a gain output signal based on the amplified signal. The circuit comprises a digital predistortion adaptation portion and a combiner. The digital predistortion adaptation portion can output a predistortion adaptation portion output signal. The combiner can output an error signal. The predistortion adaptation portion output signal is based on the input signal, the gain output signal and the error signal. The error signal is based on the difference between the predistorted signal and the predistortion adaptation portion output signal.

Abstract: The adaptive filtering techniques described herein allow a filter that is operating in a target domain to be trained in another domain, possibly with constraints, using the same adaptation framework used in a standard adaptive filter. As a result, the adaptation engine may be configured to run in a transform domain that is more desirable than the target domain. For example, the transform domain may be less susceptible to noise or may have more impact on the trained filter's desired results. The filter is trained in the transform domain and then the filter hardware is updated in the target domain.

Abstract: With high speed, high resolution time-interleaved (TI) analog-to-digital converters (ADCs), bandwidth mismatches between the various ADC branches can pose a significant problem. Previously, though, no adequate solution has been found. Here, a method and apparatus are provided that can calculate and compensate for bandwidth mismatches in a TI ADC, enabling a high speed, high resolution TI ADC to be produced.

Abstract: With high speed, high resolution time-interleaved (TI) analog-to-digital converters (ADCs), bandwidth mismatches between the various ADC branches can pose a significant problem. Previously, though, no adequate solution has been found. Here, a method and apparatus are provided that can calculate and compensate for bandwidth mismatches in a TI ADC, enabling a high speed, high resolution TI ADC to be produced.

Abstract: Systems and methods for power amplifier pre-distortion are provided. The systems and methods of power amplifier digital pre-distortion disclosed herein may include a generic pre-distorter architecture which can implement a variety of Volterra cross terms involving single dimension convolutions (first order dynamics). For hardware implementations, this generic pre-distorter is further fine-tuned to provide a choice between different sets of cross terms that can be selected for a given PA for optimal performance. The novel pre-distorter architecture provides flexibility to trade off memory depth for additional Volterra terms and vice versa. A further novelty is the ability to trade off both memory depth and cross terms for a higher sample rate operation, which may enable higher order non-linear pre-distortion, or support for higher signal bandwidths. A poly-phase non-linear filtering mode allows for this flexibility.

Abstract: A method of determining indices for matrix codewords in a matrix codeword codebook. The matrix codewords are adapted for communicating information between a transmitter and a receiver. The method includes retrieving from temporary storage, an eigenmode representation for a communications channel, where the eigenmode representation is based upon on a received signal precoded by a first matrix codeword. The method also includes performing a test on multiple vector codewords to identify a first vector codeword among the multiple vector codewords, where the test includes determining a relationship between the first vector codeword and the representation of an eigenmode. The first vector codeword is associated with a first vector codeword index that identifies the first vector codeword. The method also includes generating a matrix codeword index associated with a second matrix codeword in the matrix codeword codebook.

Abstract: A method of determining indicators for matrix codewords in a matrix codeword codebook, where the matrix codewords are adapted for communicating information between a transmitter and a receiver. The method includes providing a lookup table that is associated with multiple codewords that are associated with a codebook. The lookup table has m rows, and each row in the lookup table has a one-to-one correspondence with a codeword in the multiple codewords. Each row has p entries and each of the p entries holds a codeword indicator that identifies a codeword in the multiple codewords. The (i,j)th entry in the lookup table holds the codeword indicator identifying the jth most similar codeword to the codeword associated with the ith row according to a similarity metric, where 1?i?m and 1?j?p, and the m rows include a row k.

Abstract: A circuit for use with an amplification circuit having a predistortion datapath portion, a power amplifier portion and a gain portion. The predistortion datapath portion can output a predistorted signal based on the input signal. The power amplifier portion can output an amplified signal based on the predistorted signal. The gain portion can output a gain output signal based on the amplified signal. The circuit comprises a digital predistortion adaptation portion and a combiner. The digital predistortion adaptation portion can output a predistortion adaptation portion output signal. The combiner can output an error signal. The predistortion adaptation portion output signal is based on the input signal, the gain output signal and the error signal. The error signal is based on the difference between the predistorted signal and the predistortion adaptation portion output signal.

Abstract: An apparatus is provided to determine pre-distortion for a nonlinear system. The apparatus comprises a datapath and a power amplifier. The datapath employs predistortion data to generally linearized the power amplifier. To generate this predistortion data, an indirect learning circuit and a direct learning circuit can be employed. The indirect learning circuit is generally coupled to the amplifier circuit so that it can iteratively adjust predistortion data during an indirect learning mode until convergence is reached. The direct learning circuit is generally coupled to the amplifier circuit and the indirect learning circuit and that receives the input signal so that the predistortion data can be copied to the direct learning circuit from the indirect learning after convergence is reached and so that the direct learning circuit can adjust the predistortion data during a direct learning mode.

Abstract: An apparatus is provided to determine pre-distortion for a nonlinear system. The apparatus comprises a datapath and a power amplifier. The datapath employs predistortion data to generally linearized the power amplifier. To generate this predistortion data, an indirect learning circuit and a direct learning circuit can be employed. The indirect learning circuit is generally coupled to the amplifier circuit so that it can iteratively adjust predistortion data during an indirect learning mode until convergence is reached. The direct learning circuit is generally coupled to the amplifier circuit and the indirect learning circuit and that receives the input signal so that the predistortion data can be copied to the direct learning circuit from the indirect learning after convergence is reached and so that the direct learning circuit can adjust the predistortion data during a direct learning mode.

Abstract: A method of determining indices for matrix codewords in a matrix codeword codebook. The matrix codewords are adapted for communicating information between a transmitter and a receiver. The method includes retrieving from temporary storage, an eigenmode representation for a communications channel, where the eigenmode representation is based upon on a received signal precoded by a first matrix codeword. The method also includes performing a test on multiple vector codewords to identify a first vector codeword among the multiple vector codewords, where the test includes determining a relationship between the first vector codeword and the representation of an eigenmode. The first vector codeword is associated with a first vector codeword index that identifies the first vector codeword. The method also includes generating a matrix codeword index associated with a second matrix codeword in the matrix codeword codebook.

Abstract: A method of determining indicators for matrix codewords in a matrix codeword codebook, where the matrix codewords are adapted for communicating information between a transmitter and a receiver. The method includes providing a lookup table that is associated with multiple codewords that are associated with a codebook. The lookup table has m rows, and each row in the lookup table has a one-to-one correspondence with a codeword in the multiple codewords. Each row has p entries and each of the p entries holds a codeword indicator that identifies a codeword in the multiple codewords. The (i,j)th entry in the lookup table holds the codeword indicator identifying the jth most similar codeword to the codeword associated with the ith row according to a similarity metric, where 1?i?m and 1?j?p, and the m rows include a row k.

Abstract: A system and method for filtering communications between a sender and a recipient based on information stored in a database. The system comprises a client program, a web service program and a web interface for entering information to the database.