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OFDM modulation

`[`

performs
DC subcarrier insertion, inverse fast Fourier transform (IFFT) calculation,
cyclic prefix insertion, and optional raised cosine windowing and
overlapping of adjacent OFDM symbols of the complex symbols in the
resource array, `waveform`

,`info`

]
= lteOFDMModulate(`enb`

,`grid`

)`grid`

. `grid`

is
a 3-D array containing the resource elements (REs) for a number of
subframes across all configured antenna ports, as described in Represent Resource Grids. It could
also be multiple concatenated matrices to give multiple subframes,
using concatenation across the columns or second dimension. The antenna
planes in `grid`

are each OFDM modulated to yield
the columns of the output `waveform`

.

`grid`

can span multiple subframes. Windowing
and overlapping are applied between all adjacent OFDM symbols, including
the last of one subframe and the first of the next. Therefore, a different
result is obtained than if `lteOFDMModulate`

is
called on individual subframes and then those time-domain waveforms
are concatenated. In that case, the resulting waveform has discontinuities
at the start or end of each subframe. It is recommended that all subframes
for OFDM modulation first be concatenated before calling `lteOFDMModulate`

on
the resulting multi-subframe array. However, individual subframes
can be OFDM modulated and the resulting multi-subframe time-domain
waveform created by manual overlapping.

[1] 3GPP TS 36.101. “Evolved Universal Terrestrial Radio Access
(E-UTRA); User Equipment (UE) Radio Transmission and Reception.” *3rd
Generation Partnership Project; Technical Specification Group Radio Access
Network*. URL: https://www.3gpp.org.

`lteOFDMDemodulate`

| `lteOFDMInfo`

| `lteDLResourceGrid`

| `lteFadingChannel`

| `lteHSTChannel`

| `lteMovingChannel`