METHODS AND APPARATUS FOR COMPACTLY DESCRIBING LIFTED LOW-DENSITY PARITY-CHECK (LDPC) CODES

Abstract

ABSTRACT “METHODS AND APPARATUS FOR COMPACTLY DESCRIBING LIFTED LOWDENSITY PARITY-CHECK (LDPC) CODES” Certain aspects of the present disclosure generally relate to techniques for compactly describing lifted quasi-cyclic low-density parity-check (LDPC) codes. A method for wireless communications by a transmitting device generally includes selecting a first lifting size value Z and a first set of lifting values for generating a first lifted LDPC code (1302). The first lifted LDPC code is generated by applying the first set of lifting values to interconnect edges in Z copies of a base parity check matrix (PCM) to obtain a first lifted PCM corresponding to the first lifted LDPC code (1304). The method further includes determining a second set of lifting values for generating a second lifted PCM corresponding to a second lifted LDPC code for a second lifting size value based on the first set of lifting values (1306), encoding a set of information bits based on at least one of the first lifted LDPC code or the second lifted LDPC code to produce a code word (1308) and transmitting the code word (1310). [Fig. 13]

Specification

CLAIMS
1. A method for wireless communications, comprising: selecting a first lifting size value Z and a first set of lifting values for generating a first lifted low density parity check (LDPC) code; generating the first lifted LDPC code by applying the first set of lifting values to interconnect edges in Z copies of a base parity check matrix (PCM) having a first number of base variable nodes and a second number of base check nodes to obtain a first lifted PCM corresponding to the first lifted LDPC code; determining a second set of lifting values for generating a second lifted PCM corresponding to a second lifted LDPC code for a second lifting size value based on the first lifted PCM and the first set of lifting values; encoding a set of information bits based on at least one of: the first lifted LDPC code or the second lifted LDPC code to produce a code word; and transmitting the code word.
2. The method of claim 1, further comprising: determining a tower of lifting size values by applying a range of powers of an integer to a range of lifting size values, wherein the tower of lifting size values comprises a plurality of sets of lifting size values.
3. The method of claim 2, wherein each set of lifting size values comprises the set of lifting size values corresponding to the range of powers of the integer applied to one lifting size value of the range of lifting size values.
4. The method of claim 2, wherein selecting the first lifting size value comprises selecting a largest lifting size value in each set of lifting size values.
5. The method of claim 2, further comprising: storing only the lifted PCMs corresponding to the largest lifting size value in each set of lifting size values.
6. The method of claim 2, wherein:the second lifting size value is in a same set as the first lifting size value; and determining the second set of lifting values is based on a function involving the first set of lifting values and the second lifting size value.
7. The method

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