I want to find a tool like omnipeek on my ubuntu precise, but didn't find.
Which tools can be used to capture WLAN packets on Linux?
Wireshark is a relatively popular tool, and works on a few flavors of Linux, as well as Mac and Windows
Looks like it's also in the repos
sudo apt-get install wireshark
If you already have and use Omnipeek... Use wireshark/dumpcap or even tcpdump on your Linux system to capture the packets to a PCAPNG format to be analysed in Omnipeek.