Wireshark-users: [Wireshark-users] I CANNOT see corrupted packet

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From: SangHyuk Kim <tkdgur7896@xxxxxxxxx>
Date: Thu, 1 Sep 2016 09:46:10 +0900
Dear ALL,

I'm trying to sniff corrupted packet using Wireshark.

The test environment is :
 - TX : Ubuntu OS, ath9k_htc driver, Wireshark promiscuous mode
 - RX : Ubuntu OS, ath9k_htc driver, Wireshark promiscuous mode
 - Sniffer : Ubuntu OS, ath9k_ar9003 driver, Wireshark monitor mode
 
I set FCS(Frame Check Sequence) value to wrong for making corrupted packet
Also to capture corrupted packet, I disable CRC check filtering at sniffer machine

Before I make corrupt packet, I can see TX<->RX communications (ex. TCP/IP socket comm, ping req/rep)
Actually, the sniffer capture TX<->RX communications not very well. It's captured intermittently.
Why sometimes sniffer cannnot get packet from specific traffic? (yeah, other packet from other OS/driver are captured very well)

Anyway when I set FCS value to wrong, the results are :
 - TX :
   before FCS set : capture ping req/rep
   after FCS set 1. : capture ping request (no response)
   after FCS set 2. : stop ping request, capture ARP message (who has RX ip ? tell TX mac) repeatedly
- Sniffer : 
   before FCS set : capture ping req/rep
   after FCS set 1. : nothing while TX capture ping req (no resp)
   after FCS set 2. : capture many of 80211(RTS) packet from TX mac to AP mac (FCS/CRC incorrect)

I also tried to set TX RTS disable using 'iwconfig wlan_interface rts 2400' (I think it means that use RTS if transmit packet size over 2400 bytes)
However, the results are not different

How can I see corrupted packet(especially TCP/IP packet) from Wireshark ?
If you are confused or need more information, please tell me

Thanks.