# lteSCFDMAInfo

Get SC-FDMA modulation information

## Description

example

info = lteSCFDMAInfo(ue) returns the structure info, which contains information related to the single-carrier frequency-division multiplexing (SC-FDMA) modulation performed by the lteSCFDMAModulate function for the user-equipment-specific (UE-specific) settings structure, ue.

## Examples

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Initialize UE-specific settings by setting the number of resource blocks.

ue = struct('NULRB',50);

Get SC-FDMA modulation information and display the sampling rate.

info = lteSCFDMAInfo(ue);
disp(info.SamplingRate);
15360000

Get the sampling rate of an NB-IoT uplink waveform with 3.75-kHz subcarrier spacing after SC-FDMA modulation.

Specify the NB-IoT uplink subcarrier spacing.

ue.NBULSubcarrierSpacing = '3.75kHz';

Get the SC-FDMA modulation information and display the sampling rate of the time-domain waveform.

info = lteSCFDMAInfo(ue);
disp(info.SamplingRate);
1920000

## Input Arguments

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UE-specific settings, specified as a structure. The fields you specify in ue determine whether the function returns SC-FDMA modulation information for an LTE or NB-IoT configuration. To choose an LTE configuration, specify the NULRB field. To choose an NB-IoT configuration, specify the NBULSubcarrierSpacing field. The CyclicPrefixUL field is optional and is applicable only for an LTE configuration. The Windowing field is optional, and you can specify it for either an LTE or NB-IoT configuration.

Number of uplink resource blocks, ${N}_{\text{RB}}^{\text{UL}}$, specified as an integer in the interval [6, 110]. To return SC-FDMA modulation information for an LTE configuration, you must specify this field.

Data Types: double

Cyclic prefix length, specified as 'Normal' or 'Extended'. This field is optional.

#### Dependencies

This field applies only when you choose an LTE configuration by specifying the NULRB field.

Data Types: char | string

NB-IoT uplink subcarrier spacing, specified as '3.75kHz' or '15kHz'. To set a subcarrier spacing of 3.75 kHz, specify NBULSubcarrierSpacing as '3.75kHz'. To set a subcarrier spacing of 15 kHz, specify NBULSubcarrierSpacing as '15kHz'.

To return SC-FDMA modulation information for an NB-IoT configuration, you must specify this field. To indicate an LTE configuration, omit this field.

### Note

For a subcarrier spacing of 3.75 kHz, lteSCFDMAInfo supports only single-tone NB-IoT configurations.

Data Types: char | string

Number of windowing samples, specified as a nonnegative even integer. The value you specify sets the number of time-domain samples over which to apply windowing and overlapping of SC-FDMA symbols. This field is optional.

### Note

If you do not specify Windowing, lteSCFDMAInfo returns Windowing as a default value chosen as a function of NULRB (for LTE configurations) or NBULSubcarrierSpacing (for NB-IoT configurations). This behavior compromises between the effective duration of the cyclic prefix (and therefore the channel delay spread tolerance) and the spectral characteristics of the transmitted signal (not considering any additional FIR filtering).

Data Types: double

Data Types: struct

## Output Arguments

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Information related to SC-FDMA modulation, returned as a structure containing these fields.

Number of padded gap samples at the end of each time slot, returned as a positive integer. When the NBULSubcarrierSpacing field is '3.75kHz', NBULGapSamples is 144. Otherwise, NBULGapSamples is 0.

#### Dependencies

This argument is returned only when the NBULSubcarrierSpacing field of ue is specified.

Data Types: double

Cyclic prefix length, in number of time-domain samples, returned as a vector of positive integers. Each entry represents the cyclic prefix length of the corresponding orthogonal frequency-division multiplexing (OFDM) symbol in a time slot. The function returns CyclicPrefixLengths in accordance with the specified input fields shown in these tables.

LTE Configuration

NfftCyclicPrefixLengths when CyclicPrefixUL is set to 'Normal'CyclicPrefixLengths when CyclicPrefixUL is set to 'Extended')
128[10 9 9 9 9 9 9 10 9 9 9 9 9 9][32 32 32 32 32 32 32 32 32 32 32 32]
256[20 18 18 18 18 18 18 20 18 18 18 18 18 18][64 64 64 64 64 64 64 64 64 64 64 64]
512[40 36 36 36 36 36 36 40 36 36 36 36 36 36][128 128 128 128 128 128 128 128 128 128 128 128]
1024[80 72 72 72 72 72 72 80 72 72 72 72 72 72][256 256 256 256 256 256 256 256 256 256 256 256]
2048[160 144 144 144 144 144 144 160 144 144 144 144 144 144][512 512 512 512 512 512 512 512 512 512 512 512]

NB-IoT Configuration

NfftNBULSubcarrierSpacingCyclicPrefixLengths
128'15kHz'[10 9 9 9 9 9 9 10 9 9 9 9 9 9]
512'3.75kHz'[16 16 16 16 16 16 16 16 16 16 16 16 16 16]

### Note

As shown in the tables, for values of Nfft less than 2048, the entries of CyclicPrefixLengths are given by multiplying the cyclic prefix lengths when Nfft is 2048 by Nfft/2048.

Data Types: int32

Number of time-domain samples over which windowing and overlapping of SC-FDMA symbol is applied, returned as a positive integer.

Data Types: double

Number of FFT points, NFFT, returned as a positive integer.

Data Types: double

Sampling rate of SC-FDMA modulator, returned as a positive scalar. When the NBULSubcarrierSpacing field is '15kHz' or unspecified, the sampling rate of the waveform is 15000×NFFT, where NFFT is the number of fast Fourier transform (FFT) points. When you indicate an NB-IoT configuration by specifying ue.NBULSubcarrierSpacing, the sampling rate is 1.92 MHz.

Data Types: double

Data Types: struct