lteNPUSCHDRS

Generate NPUSCH DRS symbols

Syntax

[sym,stateOut] = lteNPUSCHDRS(ue,chs)

[sym,stateOut] = lteNPUSCHDRS(ue,chs,stateIn)

Description

[sym,stateOut] = lteNPUSCHDRS(ue,chs) generates sym, a column vector containing the narrowband physical uplink shared channel (NPUSCH) demodulation reference signal (DRS) symbols. The function generates sym in accordance with section 10.1.4 of [1] for user equipment (UE) settings ue and channel transmission configuration chs. The function also returns stateOut, a structure containing the encoder state for bundle transmission.

[sym,stateOut] = lteNPUSCHDRS(ue,chs,stateIn) specifies stateIn, the initial encoder state.

Examples

Generate NPUSCH DRS Symbols

Generate NPUSCH DRS symbols for a single-tone data channel.

Configure UE-specific settings.

ue = struct('NNCellID',0,'NBULSubcarrierSpacing','15kHz');

Specify a channel transmission configuration.

chs = struct('NPUSCHFormat','Data','NRep',2,'NRU',1,'NRUsc',1, ...
    'NULSlots',16,'SeqGroupHopping','On','SeqGroup',0);

Specify the initial encoder state as an empty structure, indicating the start of a bundle.

stateIn  = struct();

Generate NPUSCH DRS symbols.

for SlotIdx = 0:(chs.NRep*chs.NRU*chs.NULSlots-1)
    ue.NSlot = SlotIdx;
    [sym,stateOut] = lteNPUSCHDRS(ue,chs,stateIn);
    stateIn = stateOut;
end

Confirming that the transmission reaches the end of the bundle.

disp(stateOut.EndOfTx)

   1

Input Arguments

ue — UE-specific settings

structure

UE-specific settings, specified as a structure containing these fields.

Field	Values	Description	Data Types
NNCellID	Integer in the interval [0, 503]	Narrowband physical layer cell identity (PCI)	double
NFrame	0 (default), nonnegative integer	Frame number	double
NBULSubcarrierSpacing	'3.75kHz', '15kHz'	NB-IoT uplink subcarrier spacing To set a subcarrier spacing of 3.75 kHz, specify this field as '3.75kHz'. To set a subcarrier spacing of 15 kHz, specify this field as '15kHz'.	char, string
NSlot	Nonnegative integer	Slot number	double

Data Types: struct

chs — Channel transmission configuration

structure

Channel transmission configuration, specified as a structure containing these fields.

Field	Values	Description	Data Types
NPUSCHFormat	'Data', 'Control'	NPUSCH format To indicate that the NPUSCH carries narrowband uplink shared channel (UL-SCH) data, specify this field as 'Data'. To indicate that the NPUSCH carries uplink control information, specify this field as 'Control'.	char, string
NRUsc	1, 3, 6, 12	Number of consecutive subcarriers in a resource unit (RU) If you specify the NPUSCHFormat field as 'Control' or the NBULSubcarrierSpacing field of the ue input as '3.75kHz', then you must specify this field as 1.	double
NRep	1, 2, 4, 8, 16, 32, 64, 128	Number of repetitions for a codeword	double
NRU	1, 2, 3, 4, 5, 6, 8, 10	Number of RUs	double
NULSlots	2, 4, 8, 16	Number of slots per RU If you specify the NPUSCHFormat field as 'Control', then you must specify this field as 4. If you specify the NPUSCHFormat field as 'Data', then you must specify this field as: 16 when you specify the NRUsc field as 1 8 when you specify the NRUsc field as 3 4 when you specify the NRUsc field as 6 2 when you specify the NRUsc field as 12	double
BaseSeqIdx	Integer in the interval [0, 29] Default depends on the value of the NRUsc field	Multitone NPUSCH DRS base sequence index When you specify the NRUsc field as 3, specify this field as an integer in the interval [0, 11]. If you do not specify this field, the function sets it to the value of mod(ue.NNCellID,12). When you specify the NRUsc field as 6, specify this field as an integer in the interval [0, 13]. If you do not specify this field, the function sets it to the value of mod(ue.NNCellID,14). When you specify the NRUsc field as 12, specify this field as an integer in the interval [0, 29]. If you do not specify this field, the function sets it to the value of mod(ue.NNCellID,30). When you specify the NRUsc field as any other value, the function does not use this field. Dependencies. To enable this field, specify the NRUsc field as 3, 6, or 12.	double
SeqGroupHopping	'On' (default), 'Off'	To enable sequence-group hopping, specify this field as 'On'. To disable sequence-group hopping, specify this field as 'Off'. For more information, see section 5.5.1.3 of [1].	char, string
SeqGroup	0 (default), integer in the interval [0, 29]	Sequence-group assignment for sequence shift pattern calculation For more information, see section 10.1.4.1.3 of [1]. Dependencies. To enable this field, specify the SeqGroupHopping field as 'On'.	double
CyclicShift	0 (default), integer in the interval [0, 3]	Cyclic shift When you specify the NRUsc field as 3, specify this field as an integer in the interval [0, 2]. When you specify the NRUsc field as 6, specify this field as an integer in the interval [0, 3]. Dependencies. To enable this field, specify the NRUsc field as 3 or 6.	double

Data Types: struct

stateIn — Initial encoder state

struct() (default) | structure

Initial encoder state for bundle transmission, specified as a structure containing these fields.

Field	Values	Description	Data Types
SlotIdx	Integer in the interval [0, (chs.NRU x chs.NULSlots x chs.NRep) – 1]	Index of a slot within a bundle, in zero-based form	double
InitNSlot	Nonnegative integer	Slot number for scrambling sequence initialization	double
InitNFrame	Nonnegative integer	Frame number for scrambling sequence initialization	double
EndOfBlk	1 or true, 0 or false	End of transport block indicator	logical
EndOfTx	1 or true, 0 or false	End of bundle indicator	logical
GhpNSlot	Nonnegative integer	Slot number for the first slot in the RU	double

Data Types: struct

Output Arguments

sym — NPUSCH DRS symbols

complex-valued column vector

NPUSCH DRS symbols, returned as a complex-valued column vector.

Data Types: double
Complex Number Support: Yes

stateOut — Output encoder state

structure

Output encoder state, returned as a structure. This output contains the internal state of each transport block in these fields.

Field	Values	Description	Data Types
SlotIdx	Integer in the interval [0, (chs.NRU x chs.NULSlots x chs.NRep) – 1]	Index of a slot within a bundle, in zero-based form The function returns this field as the SlotIdx field of the stateIn input increased by one. When the SlotIdx field of the stateIn input reaches its maximum value, the function returns this field as 0. If you do not specify the SlotIdx field of the stateIn input, the function returns this field as 0. A value of 0 indicates that the transmission has reached the end of a bundle, which the function also indicates by setting the EndOfTx field to 1.	double
InitNSlot	Nonnegative integer	Slot number for scrambling sequence initialization When the slot being processed is at the initialization point, this field is equal to the NSlot field of the ue input. Otherwise, the function returns this field as one of these values. The value of the InitNSlot field of the stateIn input The value of the NSlot field of the ue input when you do not specify the InitNSlot field of the stateIn input	double
InitNFrame	Nonnegative integer	Frame number for scrambling sequence initialization When the frame being processed is at the initialization point, this field is equal to the NFrame field of the ue input. Otherwise, the function returns this field as one of these values. The value of the InitNFrame field of the stateIn input 0 when you do not specify the InitNFrame field of the stateIn input	double
EndOfBlk	1, 0	End of transport block indicator When the transmission reaches the end of a transport block, the function returns this field as 1. At the beginning of a bundle, the function resets this field.	logical
EndOfTx	1, 0	End of bundle indicator When the transmission reaches the end of a bundle, the function returns this field as 1. Otherwise, the function returns this field as 0. At the beginning of a bundle, the function resets this field.	logical
GhpNSLot	Nonnegative integer	Slot number for the first slot in the RU The function uses this field only when you specify the NPUSCHFormat field as 'Data' and the NRUsc field as 1 in the chs input.	double

Data Types: struct

More About

Bundle

A bundle in the medium access control (MAC) layer refers to the repeated transmissions of a transport block.

For more information, see Section 5.3.2.1 of [2].

Tips

To use this function for transmission of a bundle, follow these steps.

1. Call the function, optionally specifying the initial encoder state using the stateIn input. The stateOut output represents the first transmission of the transport block.

2. Call the function again, specifying the stateIn input as the stateOut output returned by the previous call to the function.

3. Repeat step 2 until the function returns the EndOfTx field of the stateOut output as 1 (true), indicating the end of the bundle.

References

[1] 3GPP TS 36.211. “Physical channels and modulation.” 3rd Generation Partnership Project; Technical Specification Group Radio Access Network; Evolved Universal Terrestrial Radio Access (E-UTRA). https://www.3gpp.org.

[2] 3GPP TS 36.321. “Medium Access Control (MAC) protocol specification.” 3rd Generation Partnership Project; Technical Specification Group Radio Access Network; Evolved Universal Terrestrial Radio Access (E-UTRA). https://www.3gpp.org.

Version History

Introduced in R2020a