lteRateMatchTurbo

Turbo rate matching

Syntax

out = lteRateMatchTurbo(in,outlen,rv)

out = lteRateMatchTurbo(in,outlen,rv,chs)

Description

out = lteRateMatchTurbo(in,outlen,rv) performs rate matching of input data in to create the output vector out with length outlen. The function performs subblock interleaving, bit collection and bit selection, and pruning defined for turbo encoded data. For more information, see Section 5.1.4.1 of [1].

The specified rv controls the redundancy version of the output. The bit selection stage assumes a quadrature phase-shift keying (QPSK) transmission mapped onto a single layer and no restriction on the number of soft bits, as in an uplink shared channel (UL-SCH).

out = lteRateMatchTurbo(in,outlen,rv,chs) allows additional control of the bit selection stage through selection of parameters for the soft buffer size and physical channel configuration in the chs input structure.

Examples

Perform Turbo Rate Matching

Rate match an input vector of 132 bits to a length of 100 with the RV parameter set to 0.

codedBlklen = 132;
invec = ones(codedBlklen,1);
outlen = 100;
rv = 0;

rmatched = lteRateMatchTurbo(invec,outlen,rv);
size(rmatched)

ans = 1×2

   100     1

Input Arguments

in — Input data

vector | cell array of vectors

Input data, specified as a vector or a cell array of vectors, assumed to be code blocks.

If you specify this input as a cell array, the function rate matches each vector separately and concatenates the results a single output vector out. The length of each nonempty input vector must be an integer multiple of 3.

The function treats negative values in this input as <NULL> filler buts inserted during code block segmentation, and does not process them during rate matching.

Example: ones(132,1)

Data Types: double | cell

outlen — Output vector length

nonnegative integer

Output vector length, specified as a nonnegative integer.

Data Types: double

rv — Redundancy version control

0 | 1 | 2 | 3

Redundancy version control, specified as 0, 1, 2, or 3.

Data Types: double

chs — Channel transmission configuration

structure

Channel transmission configuration, specified as a structure. It allows additional control of the bit selection stage through parameters for the soft buffer size and physical channel configuration.

For downlink turbo coded transport channels, you can control the soft buffer dimensions by including either NIR or the combined set of NSoftbits, TxScheme, and DuplexMode. If DuplexMode is 'TDD', also specify TDDConfig. If included, NIR, takes precedence for controlling the soft buffer dimensions. When neither of these optional chs fields (NIR or the set including NSoftbits) are present, the function assumes an uplink turbo coded transport channel and places no limit on the number of soft bits.

chs can contain the following fields.

Modulation — Modulation scheme

'QPSK' | '16QAM' | '64QAM' | '256QAM' | '1024QAM'

Modulation scheme, specified as 'QPSK', '16QAM', '64QAM', '256QAM', or '1024QAM'.

Data Types: char | string

NLayers — Number of transmission layers for transport block

1 (default) | positive integer

Number of transmission layers for transport block, specified as a positive integer in the interval [1, 8]. Not necessary if TxScheme is set to 'Port0', 'TxDiversity', or 'Port5'.

Data Types: double

TxScheme — Transmission scheme

'Port0' (default) | 'TxDiversity' | 'CDD' | 'SpatialMux' | 'MultiUser' | 'Port5' | 'Port7-8' | 'Port8' | 'Port7-14' | optional

PDSCH transmission scheme, specified as one of the following options.

Transmission scheme	Description
'Port0'	Single antenna port, port 0
'TxDiversity'	Transmit diversity
'CDD'	Large delay cyclic delay diversity scheme
'SpatialMux'	Closed loop spatial multiplexing
'MultiUser'	Multi-user MIMO
'Port5'	Single-antenna port, port 5
'Port7-8'	Single-antenna port, port 7, when NLayers = 1. Dual layer transmission, ports 7 and 8, when NLayers = 2.
'Port8'	Single-antenna port, port 8
'Port7-14'	Up to eight layer transmission, ports 7–14

Data Types: char | string

NIR — Soft buffer size for entire input transport block

nonnegative integer

Soft buffer size for entire input transport block, specified as a nonnegative integer.

Data Types: double

NSoftbits — Total number of soft channel bits

nonnegative integer

Total number of soft channel bits, specified as a nonnegative integer.

Data Types: double

DuplexMode — Duplex mode

'FDD' (default) | optional | 'TDD'

Duplex mode, specified as 'FDD' or 'TDD'.

Data Types: char | string

TDDConfig — Uplink or downlink configuration

0 (default) | optional | nonnegative integer

Uplink or downlink configuration, specified as a nonnegative scalar integer in the interval [0, 6]. Optional. Only required if DuplexMode is set to 'TDD'.

Data Types: double

Data Types: struct

Output Arguments

out — Turbo rate matched output

numeric column vector

Turbo rate matched output, returned as a numeric column vector.

Data Types: double | uint8 | uint16 | uint32 | uint64 | int8 | int16 | int32 | int64

References

[1] 3GPP TS 36.212. “Evolved Universal Terrestrial Radio Access (E-UTRA); Multiplexing and channel coding.” 3rd Generation Partnership Project; Technical Specification Group Radio Access Network. URL: https://www.3gpp.org.

Version History

Introduced in R2013b