Version 26 (modified by murphpo, 16 years ago) (diff) |
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OFDM Reference Design History
OFDM Reference Design v11.1 (2008-Oct-18)
The code and models for this design correspond to svn rev 1111.
This project requires the latest versions of the Xilinx tools (ISE 10.1.03 + IP2, EDK 10.1.03, Sysgen 10.1.3.1386).
Download the full XPS project: OFDM_ReferenceDesign_v11.zip
Hardware Changes
- Fixed a bug in the PHY that broke MIMO mode in refdes v11, related to the faster FFT in the receiver (thanks to the Drexel guys for finding it)
Software Changes
- Updated CSMAMAC with better "routing" table (used to map node IDs to MAC addresses)
- Updated warpphy's MIMO/SISO mode switching code to include RxScaling updates
- ifdef'd in/out code to support future PHY with convolutional code support (v11.1 is uncoded - v12 will be first coded release)
OFDM Reference Design v11 (2008-Sep-2)
The code and models for this design correspond to svn rev 1064.
This project requires the latest versions of the Xilinx tools (ISE 10.1.02 + IP2, EDK 10.1.02, Sysgen 10.1.2.1250).
Download the full XPS project: OFDM_ReferenceDesign_v11.zip
Hardware Changes
- Updated clock config core to latest version (fixes bad default values for en/disabled outputs)
- Replaced ofdm_timer with new warp_timer peripheral (now includes four independent timers)
- Reworked PHY to clock Rx FFT at system clock (40MHz).
- This reduces the Rx latency by ~4µsec; DATA-ACK turnaround now 19.8µsec.
- This also helps CFO, allowing the pilot tones to apply phase corrections one OFDM symbol earlier.
- Redesigned pilot tone phase averaging to reduce intra-symbol variance.
- Re-added shared memories for flexible Tx/Rx modulation (these were removed in v10 due to Sysgen 10.1.00 limitations).
- Added User I/O board controller
- Added interrupt for UART
- Connected reset for secondary PLB46 (fixing bug found by patel_gaurav90)
Software Changes
- New RTS/CTS implementation by Keith Wilhelm (undergrad intern in the CMC Lab)
- Updated WARPMAC/WARPPHY with support for PHY changes
- Updated timer wrapper functions for new warp_timer hardware
- Updated modulation control function for new buffer structure
- New UART ISR and user callback registration functions
- New debug "MAC" top-level code to control/observe/debug PHY in hardware
- Added basic Rx statistics display via the User I/O board LCD screen
- Moved interactive debug menu to UART interrupt callback (instead of in main while(1) loop)
- Updated AGC thresholds to better values (based on empirical tests)
- Fixed support for MIMO mode in WARPMAC/WARPPHY (now correctly calculates PHY parameters in either SISO or MIMO mode)
OFDM Reference Design v10 (2008-Jul-17)
- Known issue: see this forum post for details; this will be fixed in ref design v11
- Download the XPS project: OFDM_ReferenceDesign_v10.zip
- Built using cores and code as of repository revision 1010
- This design requires version 10.1.02 of the Xilinx tools
- Data-ACK turnaround time is now 23µs (as measured by the fall of data Tx to rise of ACK Tx)
Hardware Changes
- Xilinx deprecated the OPB and PLB34 busses. PLB46 is the new (and only) bus standard used in this design
- The System Generator cores (OFDM transceiver, timer, packet detector & AGC) were created using Sysgen's new PLB46 export flow; sysgen2opb is no longer required
- Xilinx did not port the plb_ethernet EMAC forward to PLB46. This design uses the xps_ethernetlite EMAC instead, customized to enable promiscuous mode (i.e. no receive address filtering)
- The xps_centraldma pcore is used to handle DMA (since the EMAC no longer provides its own DMA)
- The OFDM transceiver has a new interrupt output indicating the reception of a bad header
- Fixed a few logic bugs in the transceiver's handling of multiple interrupts
- Merged all user I/O into single GPIO core (LEDs, hex displays, push buttons & DIP switch); a header file helps with the required bit masking/shifting. The XBD files have been updated to use the same user I/O scheme.
Software Changes
- Ethernet is now operated exclusively in a polling mode for increased performance
- WARPMAC/WARPPHY re-architected and cleaned; the code flows for transmitting and receiving packets are now consistent across various packet types
- A layer of register access macros was added between WARPPHY and the OFDM cores; these macros adapt the old sysgen2opb register access code to the new Sysgen PLB46 export code. These macros will retired in a future revision.
OFDM Reference Design v09 (2008-Jun-11)
- Download the XPS project: OFDM_ReferenceDesign_v09.zip
- Built using cores and code as of repository revision 906
- This version assumes a different location for TxDCO calibration information in the EEPROM of the radios. Please re-calibrate before running (instructions are here)
- This will be the last reference design that will use the version 9 Xilinx tools. Reference Design v10 will use the version 10 Xilinx tools.
- Updated warpmac/warpphy & csmamac
- Header interrupts are used to pipeline receive processions (i.e. an ACK is constructed and loaded into a PHY before the packet is even completely received)
- Fall of Tx data to rise of Tx ACK turn-around time reduced from 80 microseconds to 30 microseconds
- By default, left and right push buttons use left and right radios respectively (only for MIMO WARP kits)
- Numerous tweaks to MAC timing parameters
OFDM Reference Design v08 (2008-Feb-08)
- Download the XPS project: OFDM_ReferenceDesign_v08.zip
- Built using cores and code as of repository revision 834
- Updated OFDM PHY
- Added support for header-only packets (like ACKs); numFullRateSymbols can be zero
- Last two bytes of header are now a 16-bit CRC of just the header
- Added new interrupt output for good header; asserts for non-header-only packets when header CRC passes
- Added TxDone interrupt output; asserts when a packet transmission finishes
- Fixed bugs in dynamic modulation mask usage
- Updated warpmac/warpphy & csmamac
- Changes to support new PHY features
- Added TxDone & GoodHeader interrupt handlers; unused in this version
- Added lots of comments to the source code to better explain various MAC/PHY interactions