have same project now

[jumbo77]

https://github.com/libc0607/yjsnpi-broadcast-openwrt

[moluav]

hi，booo.How is the test effect?

[booo]

@jumbo77 Sorry, your ticket got lost. Nice that you ported wifibroadcast as well. Looks really good!

@moluav What do you mean? Right now we prepare a "proper" test. So far we only made test on the ground with very mixed results. We will publish test results later on in the process.

[moluav]

@booo Okay thank you

[lsy512]

I downloaded your code and compiled it into openwrt, based on the QCA9531 platform. I tested and found that no data was received.Here are my steps：
1 Configure the wlan0 of the receiving end and the sending end as follows.
iwconfig wlan0 down
iw dev wlan0 set monitor otherbss fcsfail
ifconfig wlan0 up
iwconfig wlan0 channel 13

2 The sender executes tx wlan0 -s "32222"
3 The receiving end executes rx wlan0
4 The receiving end executes rx_status_test
5 The output of rx_status_test is as follows
Card 0

Signal: 0dBm
Received Pkg: 0
Wrong CRC ad0: 0
Lost pakets count: 0

Wifibroadcast

Wifi cards: 1
Received Blocks: 0
Damaged Blocks: 0
Used FEC pakets: 0

It looks like there is no data received. Could you tell me what went wrong?
thanks!

[booo]

You have to tell the system to disable the bpf jit with sysctl net.core.bpf_jit_enable=0.

[lsy512]

I executed the code you mentioned on the router, and it is still in the state just now. I guess there is a problem with my data input. I now bring the input directly after the tx command, is this correct? If it is not right, please tell me how to input the data into tx for him to send it out. I see in the program that it seems to be reading data from fifo, do I need to write a separate program to write the data to fifo before it can be verified? Thank you

[booo]

Right now I don't have the intention to provide a proper openwrt package for our version of wifibroadcast. We use this package for our tests only.

We did tests with the R11e-2HPnD from Mikrotik. It is a high power (30dBm), dual chain/MIMO card that supports LDPC and STBC coding.

For LDPC and STBC to work you have to patch the kernel. We contributed the patches for that to the linux kernel. At some point they should land in openwrt.

Our ground station was situated on a high tower above a hill. Our test drone was 30km away. With 5 MHz bandwidth, maximum output power, MCS index 1 and STBC/LDPC enable we achieved a netto data rate of 1.5 MBit/s.

Changing the bandwidth to 10 MHz we achieved data rates of up to 2.5 MBit/s.

We do plan to use this setup for a search and rescue drone in international waters. Therefore we don't care about maximum legal output power etc.

[booo]

I executed the code you mentioned on the router, and it is still in the state just now. I guess there is a problem with my data input. I now bring the input directly after the tx command, is this correct? If it is not right, please tell me how to input the data into tx for him to send it out. I see in the program that it seems to be reading data from fifo, do I need to write a separate program to write the data to fifo before it can be verified? Thank you

The easiest way to test is piping some test data into the program:

cat /dev/zero | tx wlan0

On the receiving end you can use tcpdump to check for incoming data frames with:

tcpdump -i wlan0

The jit command is for the receiving side.

[lsy512]

It sounds good, my QCA9531 also supports 30db transmit power
https://github.com/libc0607/yjsnpi-broadcast-openwrt
It seems that the transplantation was successful. I will take a closer look at his submission. Thank you.

I executed the code you mentioned on the router, and it is still in the state just now. I guess there is a problem with my data input. I now bring the input directly after the tx command, is this correct? If it is not right, please tell me how to input the data into tx for him to send it out. I see in the program that it seems to be reading data from fifo, do I need to write a separate program to write the data to fifo before it can be verified? Thank you

The easiest way to test is piping some test data into the program:

cat /dev/zero | tx wlan0

On the receiving end you can use tcpdump to check for incoming data frames with:

tcpdump -i wlan0

The jit command is for the receiving side.
Thanks, I will try later

[julled]

It sounds good, my QCA9531 also supports 30db transmit power
https://github.com/libc0607/yjsnpi-broadcast-openwrt
It seems that the transplantation was successful. I will take a closer look at his submission. Thank you.

Which hardware board do you use?

[lsy512]

It sounds good, my QCA9531 also supports 30db transmit power
https://github.com/libc0607/yjsnpi-broadcast-openwrt
It seems that the transplantation was successful. I will take a closer look at his submission. Thank you.

Which hardware board do you use?

The name of the board I use is easylink

[lsy512]

hi booo，
I successfully use cat /dev/zero | tx wlan0 to send data, and I can also use the tcpdump -i wlan0 command to see the data, but the following problem occurs when I use ./rx wlan0 to receive data:

Could not fully reconstruct block 71f7b! Damage rate: 0.999293 (4243 / 4246 blocks)
Data mis: 8 Data corr: 0 FEC mis: 3 FEC corr: 0
mmmvmmmm mmmm

Seems to be caused by packet loss.What is the reason for this?can you give me some advice？