Main Content

lteSLMIB

Sidelink MIB encoding and decoding

Description

example

mibslout = lteSLMIB(ue) returns the encoded sidelink MIB (MIB-SL) RRC message bits for the specified UE settings structure.

For more information, see MIB-SL Message Processing.

example

ueout = lteSLMIB(mibsl) performs the inverse processing of the preceding syntax, returning a UE parameter structure after decoding the input MIB-SL message bits.

example

ueout = lteSLMIB(mibsl,ue) returns the UE settings structure, updating any fields contained in the input UE parameter structure with values decoded from mibsl.

Examples

collapse all

Create the 40-bit MIB-SL associated with the parameter values to be carried on the message.

Initialize a UE-specific configuration structure with 10 MHz bandwidth for TDD.

ue.NSLRB = 50;
ue.DuplexMode = 'TDD';
ue.TDDConfig  = 6;
ue.NFrame = 5;
ue.NSubframe = 1;
ue.InCoverage = 1;

Generate the 40-bit MIB-SL message using the ue structure.

mibsl = lteSLMIB(ue);

Decode the 40-bit MIB-SL message, creating a received parameter structure from the message.

Initialize a UE-specific configuration structure with 5 MHz bandwidth for TDD.

ue.NSLRB = 25;
ue.DuplexMode = 'TDD';
ue.TDDConfig = 6;
ue.NFrame = 5;
ue.NSubframe = 1;
ue.InCoverage = 1
ue = struct with fields:
         NSLRB: 25
    DuplexMode: 'TDD'
     TDDConfig: 6
        NFrame: 5
     NSubframe: 1
    InCoverage: 1

Generate the 40-bit MIB-SL message using the ue structure.

mibsl = lteSLMIB(ue);

Convert the MIB-SL bit vector back into a parameter set. Compare this parameter set with the transmission set.

rxparams = lteSLMIB(mibsl)
rxparams = struct with fields:
         NSLRB: 25
    DuplexMode: 'TDD'
     TDDConfig: 6
        NFrame: 5
     NSubframe: 1
    InCoverage: 1

isequal(rxparams,ue)
ans = logical
   1

Update UE-specific parameter configuration structure settings using the 40-bit MIB-SL message. Encode an MIB-SL message based on one ue structure parameter set.

Encode an MIB-SL message from one UE-specific configuration

Initialize a UE-specific configuration structure with 5 MHz bandwidth for TDD. Encode a 40-bit MIB-SL message using the ue1 structure.

ue1.NSLRB = 25;
ue1.DuplexMode = 'TDD';
ue1.TDDConfig = 6;
ue1.NFrame = 5;
ue1.NSubframe = 1;
ue1.InCoverage = 1;

mibsl = lteSLMIB(ue1);

Create a second UE-specific configuration

Initialize a second UE-specific configuration structure with a different configuration. Compare ue2 with ue1.

ue2.NSLRB = 75;
ue2.DuplexMode = 'TDD';
ue2.TDDConfig = 2;
ue2.NFrame = 2;
ue2.NSubframe = 2;
ue2.InCoverage = 0;

isequal(ue2,ue1)
ans = logical
   0

Update the second UE-specific configuration based on the MIB-SL message

Using mibsl, update the settings in ue2 to match ue1. Compare ue2 with ue1.

ue2 = lteSLMIB(mibsl,ue2);
isequal(ue2,ue1)
ans = logical
   1

Input Arguments

collapse all

User equipment settings, specified as a parameter structure containing these fields:

Number of sidelink resource blocks, specified as an integer scalar from 6 to 110.

Example: 6, which corresponds to a channel bandwidth of 1.4 MHz.

Data Types: double

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

Data Types: char | string

Uplink or downlink configuration, specified as an integer from 0 to 6. (tdd-ConfigSL-r12)

TDDConfig is applicable for TDD duplex mode only.

Data Types: double

Direct frame number, specified as a nonnegative integer. (directFrameNumber-r12)

Data Types: double

Direct subframe number, specified as a nonnegative integer. (directSubframeNumber-r12)

Data Types: double

Indicates whether the UE transmitting the MIB-SL is in E-UTRAN coverage, specified as 0 (not in coverage) or 1 (in coverage). (inCoverage-r12).

Data Types: double

Data Types: struct

MIB-SL message bit sequence, specified as a 40-bit column vector.

For more information, see MIB-SL Message Processing.

Data Types: double | int8 | logical

Output Arguments

collapse all

MIB-SL message bit sequence, returned as a 40-bit column vector.

For more information, see MIB-SL Message Processing.

Data Types: int8

User equipment settings, returned as a parameter structure containing these fields:

Number of sidelink resource blocks, returned as an integer from the set {0, 6, 15, 25, 50, 75, 100}. (NRBSL)

For more information on sidelink bandwidths, see MIB-SL Message Processing.

Data Types: int32

Duplexing mode, returned as 'FDD' or 'TDD'.

Data Types: char

Uplink or downlink configuration, returned as an integer from 0 to 6. (tdd-ConfigSL-r12)

TDDConfig is applicable for TDD duplex mode only.

Data Types: int32

Direct frame number, returned as a nonnegative integer. (directFrameNumber-r12)

Data Types: int32

Direct subframe number, returned as a nonnegative integer. (directSubframeNumber-r12)

Data Types: int32

Indicates when UE is in E-UTRAN coverage, returned as 0 or 1. (inCoverage-r12) The UE transmitting the MIB-SL is:

  • Not in E-UTRAN coverage when InCoverage = 0.

  • In E-UTRAN coverage when InCoverage = 1.

Data Types: int32

Data Types: struct

More About

collapse all

MIB-SL Message Processing

The MIB-SL message is a 40 bits long and defined in TS 36.331 [1], Section 6.5.2. The message is sent from UE to UE on the PC5 interface via the SL-BCH transport channel on the SBCCH logical channel. MIB-SL contains sl-Bandwidth-r12, tdd-ConfigSL-r12, directFrameNumber-r12, directSubframeNumber-r12, inCoverage-r12, and 19 bits reserved for future.

  • When encoding the MIB-SL message:

    • If NSLRB is not one of the set {6,15,25,50,75,100}, then all ones are inserted into the first three bits (sl-Bandwidth-r12 bit field) of the MIB message.

  • When decoding the MIB-SL message:

    • If the first three bits (sl-Bandwidth-r12 bit field) of the input MIB-SL message do not contain the equivalent of a decimal from 0 to 5 (MSB first, corresponding to the PRB set {6,15,25,50,75, 100}) then NSLRB is returned as 0.

    • If the input MIB-SL messages are not 40 bits, the messages are either truncated to 40 elements or zero padded as needed.

References

[1] 3GPP TS 36.331. “Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification.” 3rd Generation Partnership Project; Technical Specification Group Radio Access Network. URL: https://www.3gpp.org.

Version History

Introduced in R2016b