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lteNBResourceGrid

Narrowband resource array

Description

example

grid = lteNBResourceGrid(cfg) generates an empty resource array for the specified configuration settings. If you specify an uplink transmission, the elements of the grid output represent elements for one slot of a narrowband internet of things (NB-IoT) resource array, as described in section 10.1.2.1 of [1]. If you specify a downlink transmission, the elements of the grid output represent elements for one subframe of an NB-IoT resource array, as described in section 10.2.2.1 of [1].

For more information about resource grids and LTE Toolbox™ resource element representation by using multidimensional arrays, see Represent Resource Grids.

Examples

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Create a resource array for an uplink NB-IoT transmission with a subcarrier spacing of 3.75 kHz and a single antenna port.

Configure a transmission with a subcarrier spacing of 3.75 kHz.

cfg = struct('NBULSubcarrierSpacing','3.75kHz');

Create the resource array and display its size.

grid = lteNBResourceGrid(cfg);
disp(size(grid))
    48     7

Specify a downlink NB-IoT configuration for one subframe and two antenna ports.

cfg = struct('NBRefP',2);

Create the resource array and display its size.

grid = lteNBResourceGrid(cfg);
disp(size(grid))
    12    14     2

Input Arguments

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Configuration settings, specified as a structure whose fields depend on the desired configuration.

To generate a resource array for an uplink configuration, the input structure must contain this field.

FieldValuesDescriptionData Type
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

To generate a resource array for a downlink configuration, the input structure must contain this field.

FieldValuesDescriptionData Type
NBRefP1, 2Number of narrowband reference signal (NRS) antenna ports.double

If you specify both fields, the function ignores the value of the NBRefP field and generates a resource array for the uplink configuration corresponding to the value of the NBULSubcarrierSpacing field.

Data Types: struct

Output Arguments

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Empty resource array, returned as an N-by-M-by-P array of zeros, where:

  • N is the number of subcarriers

  • For an uplink transmission, M is the number of single-carrier frequency-division multiple access (SC-FDMA) symbols in a slot. For a downlink transmission, M is the number of orthogonal frequency-division multiplexing (OFDM) or SC-FDMA symbols in a subframe.

  • P is the number of transmit antenna ports. For an uplink transmission, P is 1. For a downlink transmission, P is the value of cfg.NBRefP.

If you specify an uplink configuration, the elements of this output represent elements for the slot resource array described in section 10.1.2.1 of [1]. If you specify a downlink configuration, the elements of this output represent elements of the subframe resource array described in section 10.2.2.1 of [1].

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.

Introduced in R2021a