MIMO OFDM? | Documentation? | OFDM Frame Format

Overview

The frame format for the WARP MIMO OFDM core is based loosely on the frame format specified in the ​IEEE 802.11a wireless networking standard. The WARP MIMO OFDM core supports both single (SISO) and two antenna (MIMO) modes. The frame formats for these two modes are detailed below.

Each frame is divided into four sections, illustrated below:

Preamble

A hard-coded 320-sample sequence used by the receiver for AGC, carrier frequency offset estimation and symbol timing estimation ofdm_tx_mimo_init

Training

A hard-coded OFDM symbols used for channel estimation. The number of training symbol periods is programmable per-packet. ofdm_tx_mimo_init

Base Rate

A programmable number of OFDM symbols containing a packet's header, modulated using the user-specified base-rate modulation scheme. ResearchApps/PHY/MIMO_OFDM/ofdm_tx_mimo_init.m#L150

Full Rate

A programmable number of OFDM symbols containing a packet's payload, modulated using the user-specified full-rate modulation scheme. ResearchApps/PHY/MIMO_OFDM/ofdm_tx_mimo_init.m#L150

SISO Frame Format

MIMO Frame Format