Patent application number | Description | Published |
20100070819 | Channel adaptive iterative turbo decoder system and method - A channel adaptive iterative turbo decoder for computing with MAP decoders a set of branch metrics for a window of received data, computing the forward and reverse recursive path state metrics and computing from the forward and reverse recursive path state metrics the log likelihood ratio for 1 and 0 and interleaving the decision bits; and identifying those MAP decoder decision bits which are non-convergent, computing a set of branch metrics for the received data, computing from the forward and reverse recursive path state metrics the log likelihood ratio (LLR) for 1 and 0 for each non-converged decision bit and interleaving the non-convergent decision bits. | 03-18-2010 |
20110026577 | Equalization for OFDM Communication - The problem of inefficient channel impulse-response processing is addressed by processing different parts of a channel impulse response to accurately locate channel taps, and to generate more than one set of equalization coefficients. This allows the most-suited equalization coefficient to be selected based on a selection criterion. | 02-03-2011 |
20110103450 | OFDM CHANNEL ESTIMATION SYSTEM AND METHOD COMPONENTS - Channel estimation for high mobility OFDM channels is achieved by identifying a set of channel path delays from an OFDM symbol stream including carrier data, inter-channel interference noise and channel noise; determining the average channel impulse response for the identified set of channel path delays in each symbol; generating a path delay curvature for each channel path delay in each symbol based on stored average channel impulse responses for the identified channel path delays; estimating the carrier data in the symbols in the OFDM symbol stream in the presence of inter-channel interference noise and channel noise from the OFDM symbol steam and the average impulse responses for the identified channel path delays; reconstructing the inter-channel interference noise in response to the path delay curvature, the identified set of channel path delays and estimated carrier data to produce a symbol stream of carrier data and channel noise with suppressed inter-channel interference noise. | 05-05-2011 |
20110103453 | OFDMCHANNEL ESTIMATION SYSTEM AND METHOD COMPONENTS - Channel estimation for high mobility OFDM channels is achieved by identifying a set of channel path delays from an OFDM symbol stream including carrier data, inter-channel interference noise and channel noise; determining the average channel impulse response for the identified set of channel path delays in each symbol; generating a path delay curvature for each channel path delay in each symbol based on stored average channel impulse responses for the identified channel path delays; estimating the carrier data in the symbols in the OFDM symbol stream in the presence of inter-channel interference noise and channel noise from the OFDM symbol steam and the average impulse responses for the identified channel path delays; reconstructing the inter-channel interference noise in response to the path delay curvature, the identified set of channel path delays and estimated carrier data to produce a symbol stream of carrier data and channel noise with suppressed inter-channel interference noise. | 05-05-2011 |
20110182340 | OFDM CHANNEL ESTIMATION SYSTEM AND METHOD COMPONENTS - Channel estimation for high mobility OFDM channels is achieved by identifying a set of channel path delays from an OFDM symbol stream including carrier data, inter-channel interference noise and channel noise; determining the average channel impulse response for the identified set of channel path delays in each symbol; generating a path delay curvature for each channel path delay in each symbol based on stored average channel impulse responses for the identified channel path delays; estimating the carrier data in the symbols in the OFDM symbol stream in the presence of inter-channel interference noise and channel noise from the OFDM symbol steam and the average impulse responses for the identified channel path delays; reconstructing the inter-channel interference noise in response to the path delay curvature, the identified set of channel path delays and estimated carrier data to produce a symbol stream of carrier data and channel noise with suppressed inter-channel interference noise. | 07-28-2011 |
20110182374 | OFDM CHANNEL ESTIMATION SYSTEM AND METHOD COMPONENTS - Channel estimation for high mobility OFDM channels is achieved by identifying a set of channel path delays from an OFDM symbol stream including carrier data, inter-channel interference noise and channel noise; determining the average channel impulse response for the identified set of channel path delays in each symbol; generating a path delay curvature for each channel path delay in each symbol based on stored average channel impulse responses for the identified channel path delays; estimating the carrier data in the symbols in the OFDM symbol stream in the presence of inter-channel interference noise and channel noise from the OFDM symbol steam and the average impulse responses for the identified channel path delays; reconstructing the inter-channel interference noise in response to the path delay curvature, the identified set of channel path delays and estimated carrier data to produce a symbol stream of carrier data and channel noise with suppressed inter-channel interference noise. | 07-28-2011 |
Patent application number | Description | Published |
20140270018 | CIRCUIT ARCHITECTURE FOR I/Q MISMATCH MITIGATION IN DIRECT CONVERSION RECEIVERS - An electrical circuit includes a local oscillator configured to generate a first reference signal and a second reference signal having a predetermined phase shift with the first reference signal, an I-channel mixer configured to inject the first reference signal to an incoming signal and generate a first output, a compensation mixer configured to multiply the first output with a constant factor to generate a second output, a first low pass filter configured to approximately attenuate frequencies in the second output to generate a third output, and a first correcting filter configured to filter the third output to generate a fourth output. The first correcting filter is configured to reduce a channel impulse response mismatch between the first low pass filter and a second low pass filter, which is configured to attenuate frequencies in a Q-channel of the incoming signal. In specific embodiments, the phase shift includes 45°. | 09-18-2014 |
20150113359 | MULTI-LAYER ERROR CORRECTING CODING - A transmission system may include a transformer, an adder, an encoder, and a transmitter. The transformer may segment and transform a data packet into segments. The adder may add a check code to each of the segments. The encoder may encode error correction to each of the segments with the added check code. A receiving system may include a receiver, a decoder, a checker, and a selector decoder. The decoder may decode error correction in each of the encoded segments. The checker may check the check code of the error corrected segments. The selector decoder may select at least one of the valid segments based upon the check code and transform the selected segments into a data packet. | 04-23-2015 |
20150131705 | MODULATION SCHEME FOR COMMUNICATION - A modulation scheme for long range transceiver utilizing a processing scheme in combination with a Hadamard transform is disclosed. The processing scheme can correspond to an industry standard or to other processing schemes. An input signal is parallelized through serial to parallel conversion. The processed parallel signals are orthogonalized using a Hadamard transform to allow multiple channel signals with increased throughput. Accordingly, the long range modulation scheme of this invention can achieve high efficiency and increased throughput while meeting performance goals of long range signal transmission. | 05-14-2015 |