Quantenna Communications, Inc.

Fredrik Brannstrom

Andrea Goldsmith

Behrooz Rezvani

Farrokh Farrokhi

A technique for low-density parity-check (LDPC) coding involves utilizing a fixed point implementation in order to reduce or eliminate reliance on floating point operations. The fixed point implementation can be used to calculate check node extrinsic L-value as part of an LDPC decoder in an LDPC system. The technique can include one or more of linear approximations, offset approximations, and node-limiting approximation. A system constructed according to the technique implements one or more of linear approximations, offset approximations, and node-limiting approximation.

Low complexity LDCP decoding

A technique weights noise power used in a demodulation/demapping process using on an estimate of interference and its associated power. Using this technique the effect of partial interference can be ameliorated. For example, a value, &#x3c3;, can be used to represent the estimated noise and interference power, and &#x3c3;can be used to modify a received signal to ameliorate the effects of noise and interference. &#x3c3;can be adjusted in response to partial interference, and can be represented by the formula: &#x3c3;=&#x3c3;+q &#x3c3;, where &#x3c3;is 'noise power,' &#x3c3;is 'interference power,' and q is an interference correction factor.

Mitigating interference in a coded communication system

A technique for low-complexity high-performance coherent demodulation of GFSK signals involves utilizing a novel phase and frequency tracking mechanism coupled with a trellis search technique to track signal memory in the demodulation process. A method according to the technique may include modeling modulation based upon a trellis. The method may further include estimating unknown parameters, selecting a maximum likelihood path through the trellis, and mapping the maximum likelihood path to an output bit sequence. The technique is also applicable to DSPK and other applicable known or convenient protocols.

Demodulation technique for GFSK and DPSK

A device including a minimal trellis decoder is disclosed. The device can receive an encoded codeword, which the minimal trellis decoder efficiently decodes. In a specific implementation, the device can include a Bluetooth receiver that, in operation, receives an encoded codeword from a Bluetooth transmitter, which is decoded by the minimal trellis decoder.

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Mountain View, CA, United States of America

Fredrik Brannstrom