Re: [Discuss-gnuradio] why can't use iwconfig when I run the gr-ieee802-11

[zhan siyu]

Thanks. I just wonder why. Because I meet some performance problem. I thought it maybe caused by my misconfiguration of the gr-ieee802-11 code. Now, it seems not.

However, theoretically,  as my current sample rate is 10M and BPSK. So the coding rate should be 10M/2 = 5M b/s. The throughtput should be around 5M/8 = 625K B/s. Assuming the 12% head cost, so the data throughput should be 625 * 88 % = 550K B/s.  But as my experiment shows, the throughput is only 150K B/s.

I'm new to the communication. Is my calculation right ? If it were right, then what might cause the gap?

One more question, I didn't run the volk_profile. Does it matter?

Best regards.

Siyu

2017-06-07 4:23 GMT+08:00 Bastian Bloessl <address@hidden>:

Hi,

On 06/06/2017 03:55 PM, zhan siyu wrote:

Hi all,

I just found I can't use the iwconfig tap0 rate 20M to setup the bandwidth of the tap0. The error message is :

Error for wireless request "Set Bit Rate" (8B20) :
          SET failed on device tap0 ; Operation not supported.

But in their video , it can be set in this way. May I know how to solve it ?

The WiFi transceiver is attached to the tun/tap interface, which is a virtual Ethernet device. This device doesn't support WiFi-specific configuration through iwconfig.

If you wanted this level of integration, you would have to write a kernel module that attaches the transceiver to a virtual WiFi card.

Some group already did that, but they didn't release the source code.

Best,
Bastian