# ofdmmod

Modulate frequency-domain signal using orthogonal frequency division multiplexing (OFDM)

## Syntax

## Description

performs OFDM modulation on the frequency-domain input data subcarriers,
`ofdmSig`

= ofdmmod(`inSym`

,`nfft`

,`cplen`

)`inSym`

, using an FFT size specified by
`nfft`

and cyclic prefix length specified by
`cplen`

. For information, see OFDM Modulation.

inserts null subcarriers into the frequency domain input data signal prior to
performing OFDM modulation. The null subcarriers are inserted at index locations
from 1 to `ofdmSig`

= ofdmmod(`inSym`

,`nfft`

,`cplen`

,`nullidx`

)`nfft`

, as specified by `nullidx`

.
For this syntax, the number of rows in the input `inSym`

must be
`nfft`

–
`length(`

. Use null carriers to
account for guard bands and DC subcarriers. For information, see Subcarrier Allocation, Guard Bands and Guard Intervals.`nullidx`

)

inserts null and pilot subcarriers into the frequency domain input data symbols
prior to performing OFDM modulation. The null subcarriers are inserted at the index
locations specified by `ofdmSig`

= ofdmmod(`inSym`

,`nfft`

,`cplen`

,`nullidx`

,`pilotidx`

,`pilots`

)`nullidx`

. The pilot subcarriers,
`pilots`

, are inserted at the index locations specified by
`pilotidx`

. For this syntax, the number of rows in the input
`inSym`

must be `nfft`

–
`length(`

–
`nullidx`

)`length(`

. The function
assumes pilot subcarrier locations are the same across each OFDM symbol and transmit
antenna.`pilotidx`

)

## Examples

## Input Arguments

## Output Arguments

## More About

## Extended Capabilities

**Introduced in R2018a**