RACH channel coding

Files
file	rach.h
	Osmocom GMR-1 RACH channel coding header.
file	rach.c
	Osmocom GMR-1 RACH channel coding implementation.

Functions
void	gmr1_rach_encode (ubit_t *bits_e, const uint8_t *rach, uint8_t sb_mask)
	Stateless GMR-1 RACH channel coder. More...
int	gmr1_rach_decode (uint8_t *rach, const sbit_t *bits_e, uint8_t sb_mask, int *conv_rv, int *crc_rv)
	Stateless GMR-1 RACH channel decoder. More...

Detailed Description

Function Documentation

gmr1_rach_decode()

int gmr1_rach_decode	(	uint8_t *	rach,
		const sbit_t *	bits_e,
		uint8_t	sb_mask,
		int *	conv_rv,
		int *	crc_rv
	)

Stateless GMR-1 RACH channel decoder.

Parameters

[out]	rach	RACH packet data (2 class-1 bytes, 16 class-2 bytes)
[in]	bits_e	Data bits of a burst
[in]	sb_mask	RACH SB Mask value (see GMR-1 04.008)
[out]	conv_rv	Return of the convolutional decode (can be NULL)
[out]	crc_rv	Return array of the 2 CRC checks (can be NULL)

Returns

0 if all CRC check pass, any other value for fail.

RACH data is 18 bytes long (2 class-1, 16 class-2), and bits_e is a 494 soft bits array unmapped from a RACH burst.

References gmr1_deinterleave_intra(), and gmr1_scramble_sbit().

gmr1_rach_encode()

void gmr1_rach_encode	(	ubit_t *	bits_e,
		const uint8_t *	rach,
		uint8_t	sb_mask
	)

Stateless GMR-1 RACH channel coder.

Parameters

[out]	bits_e	Data bits of a burst
[in]	rach	RACH packet data (2 class-1 bytes, 16 class-2 bytes)
[in]	sb_mask	RACH SB Mask value (see GMR-1 04.008)

RACH data is 18 bytes long (2 class-1, 16 class-2), and bits_e is a 494 hard bits array to be mapped on a RACH burst.

References gmr1_crc12, and gmr1_crc8.