Changes between Version 4 and Version 5 of OFDM/MIMO/Docs/PHYDetails

Timestamp:

Aug 30, 2009, 1:12:17 PM (15 years ago)

Author:

murphpo

Comment:

--

OFDM/MIMO/Docs/PHYDetails

@@ -3 +3 @@
 The WARP MIMO OFDM core implements a real-time OFDM transceiver in the fabric of a Xilinx FPGA.
 
-== PHY Features ==
-
-=== Antenna Configurations ===
+== Antenna Configurations ==
 The OFDM PHY supports three primary antenna modes: SISO, Alamouti and 2x2 multiplexing. The antenna mode is configurable per-packet from user C code. The transmitter and receiver must agree ahead of time on the antenna mode.
 
@@ -16 +14 @@
 '''2x2 multiplexing''': this mode  uses spatial multiplexing to transmit and receive from both antennas. This scheme doubles the data rate (vs. SISO), as two symbols are transmitted with each channel use. But this mode is less reliable than SISO or Alamouti, since a given data bit is transmitted from only one antenna (diversity = 1).
 
-=== OFDM Parameters ===
+== OFDM Parameters ==
 
 The OFDM core uses 64 subcarriers, spaced evenly in the transmitted waveform. 4 subcarriers are dedicated to pilot tones. The DC subcarrier (index 0) must always be empty. The remaining subcarriers can be loaded with data modulated as BPSK, QPSK, 16-QAM or 64-QAM symbols. Any combination of modulation schemes can be used across subcarriers, though the subcarrier-modulation assignment must be fixed for a full packet.
 
 The bandwidth of the OFDM signal is 1/4 of the core's master clock. In most implementations, the master clock is sourced by the host PLB46 bus. We have tested the core with 40 and 80MHz bus clocks (corresponding to 10 and 20MHz over-the-air bandwidths).
+
+SubcarrierIndicies.png