NWACC/PSU SDR
Welcome to the Portland State
University Software Defined Radio project. This project
is led by the PSU Maseeh
College of Engineering and Computer Science and has been
funded by a generous grant from the Northwest Academic Computing
Consortium and from Google through the Google/PSU Summer of Code program.
This Wiki collaborative site is a place for project
contributors to work and for others to see what we're up to.
Our NWACC grant is $10,000 to build "Applications of Open
Software Defined Radio". The lead Principal
Investigator is PSU Prof. Bart Massey; the
other PIs are PSU Profs. Jim Binkley and Warren Harrison and
PSU student and City of Portland communications professional
Glenn
LeBrasseur. Of course, a variety of PSU students
will do the vast majority of the real work.
SDR is a cool technology. Basically, attach an absurdly
high-bandwidth DAC and/or ADC to a computer, and do all the
modulation/demodulation and encoding/decoding in software.
This gives tremendous flexibility in deployment, and great
opportunities for research and education.
One ongoing task is to identify the specific hardware we
need and select vendors. We are building on the work of the
GNU
Radio project, using their Universal
Software Radio Peripheral (USRP), TX and RX
daughterboards, and appropriate RF frontends for the
frequency bands that we care about. USRP units and basic
daughterboards are available from Ettus
Research.
Status
- 12 September 2005:
- Our Summer of Code work
students reported out September 1. This means that we have
three projects in a somewhat working state. In addition a
new undergraduate student, Jules Kongslie, got involved this
Summer and did some cool work. As a result, we currently
have 4 projects in a "working" experimental state:
- GPS Correlator (Carroll). Works on synthetic data.
Waiting for downconverters to demonstrate with USRP, but
should just work.
- 802.11 (Sharp). Baseband transmit and receive work.
We are currently worried about the USRP's quadrature
bandwidth of 60MHz and the USB 2.0 bandwidth of around
300Kb/s. While we think we can work with both of these,
we await up/downconverters to try it out with COTS 802.11
cards.
- Custom Telemetry (Bailey). Baseband transmit and
receive work, but there's a lot more design and
implementation to do here.
- Emergency Radio (Kongslie). Demonstrated fitting a
complete FM quadrature tuner/demod/decimator onto the FPGA
itself! (AM also, but this is easier.) Barely fits,
though, and some things are hard-wired that shouldn't be.
Still, this is a really cool result.
- Curriculum Development (various Faculty). Not much
progress here over the Summer. Hopefully will be easier
to pursue in the Fall.
- 02 July 2005:
- Main.JameySharp and
Main.SarahBailey just installed GNU Radio on Sarah's new
Debian system. We took notes.
- 26 June 2005:
- Today Main.JameySharp
demonstrated for the first time receiving commercial AM
radio broadcasts. We have working hardware!
- 16 June 2005:
- We received the USRPs
approximately 2 weeks ago. Unfortunately, the
BasicTX and BasicRX daughterboards were on hold.
Last night Main.JameySharp brought the USRP up and
demonstrated communication with a laptop by turning the
blinky-lights on and off. This morning, the
daughterboards arrived. We have hardware!
Project Pages
References
- Paper on FPGAs for SDR. (Thanks to Robert Bauer for the reference.)
- Definitive book on SDR GPS: Fundamentals of Global Positioning System Receivers: A Software Approach, 2nd Edition by James Bao-Yen Tsui. Make sure you get the *2nd* edition. (Thanks to Andrew Greenberg for the reference.)
- Definitive book on DSP: Discrete-Time Signal Processing, 2nd Edition by Alan V. Oppenheim, Ronald W. Schafer, and John R. Buck. You can find the second edition used softcover online in the $40 range: try e.g. half.com.