WARP Project Forums - Wireless Open-Access Research Platform

You are not logged in.

#1 2018-May-29 20:23:14

zhimeng
Member
Registered: 2015-Sep-30
Posts: 47

Is it possible to implement a MAC in WARPlab 7?

Hi, we are trying to implement a MAC protocol with the support of WARPlab 7.

The signal is generated via matlab code, and then transmitted with the corresponding commands.
At the receiver side, the received signal is demodulated with matlab.

We have finished this part, but we are curious if it is possible a MAC protocol on top of the TX/RX procedures.
For example, the sender first senses the channel energy, and then delays the transmission if the channel is busy, similar to CSMA.
We are not sure if WARPlab supports this strict latency application.

Could you please comment on this?

Offline

 

#2 2018-May-30 10:30:25

murphpo
Administrator
From: Mango Communications
Registered: 2006-Jul-03
Posts: 4954

Re: Is it possible to implement a MAC in WARPlab 7?

The WARPLab Reference Design by itself is not very useful for MAC experiments. The latency from antenna (hardware) to PHY (M code) is long and jittery, which precludes normal real-time MAC behaviors.

For example, the sender first senses the channel energy, and then delays the transmission if the channel is busy, similar to CSMA.

This specific behavior could be added to WARPLab by modifying the WARPLab FPGA design. By default the WARPLab FPGA design starts a Tx when it receives a trigger via Ethernet. You could add a new Tx mode where the Tx state machine starts only when the medium goes idle. The transmitted waveform could still be generated in M code and transferred via Ethernet. You could use the RSSI signal as a proxy for medium activity. We've never attempted this modification, so I can't provide specific instructions on how to implement it.

Offline

 

#3 2018-May-30 10:40:58

zhimeng
Member
Registered: 2015-Sep-30
Posts: 47

Re: Is it possible to implement a MAC in WARPlab 7?

Thanks so much for the detailed feedback!
We are trying these methods now.

Offline

 

Board footer