15-849: Cognitive Networking - Possible CR Platforms

The project requires a flexible wireless network interface with both rich monitoring capability and options for adapting wireless communciation. Here are some options:

• The USRP platform and GNURadio: The advantage of USRP/GNURadio is its flexibility. The primary drawback is low performance both in terms of bandwidth (8 MHz) and processing capabilities (host only). Also, GNURadio support for MAC protocols is limited, although CMU has done a lot of work in this area. We have several USRP platforms available and the wireless emulator testbed also has a number of USRP devices. Readings include: GNU Radio overview , GNU radio web site , USRP , Enabling MAC Protocol Implementations on Software-defined Radios, and Supporting Integrated MAC and PHY Software Development for the USRP SDR. The last paper is an older paper that might give you ideas on possible projects. Its software is not availble.
• USRP 2 is a faster version of the USRP (http://www.ettus.com/download ). The primary drawback is that all processing is still done on the host, and hosts have trouble keeping up with the card. It is possible to overcome this using decimation.
• Commercial WiFi cards can be used for wireless experiments. A number of packages have been developed that make it possible to implement non-standard MACs on WiFi cards based on the Atheros chip set. Examples include: Softmac , MultiMac , MadMac , and FlexMac . FlexMac is available. You would need to check for others.
• It is possible to change the bandwidth of the signal emitted by WiFi cards (using Atheros) to 5 MHz, and 10 MHz, besides the standard 20 MHz. An interesting paper in this context is A Case for Adapting Channel Width in Wireless Networks. There are also some interesting follow on papers, including the White Space paper assigned for Monday Sep 14.