Help----Has anyone test MIPL with wireless USB adapter under linux-wlan-ng driver?

Hi

    I use D-link DWL122 wireless USB adapter and set up a MIPL wireless test-bed.But the 

handover delay is too long.I can only use the "wlanctl-ng" command to implement handover:

    wlanctl-ng wlan0 lnxreq_ifstate ifstate=disable
    wlanctl-ng wlan0 lnxreq_ifstate ifstate=enable
    wlanctl-ng wlan0 dot11req_start ssid=foreignwlan bsstype=independent beaconperiod=100  timperiod=3 cfpollable=false cfpollreq=false cfpperiod=3 cfpmaxduration=100 probedelay=100 dschannel=6 basicrate1=2 basicrate2=4 operationalrate1=2 operationalrate2=4 operationalrate3=11

    But the handover delay is about 6s.From the packets I catch,I found the L2 handover took a long 

time. 

    Are there any other meathod to implement handover?How to reduce the delay?

    Any help would be appreciated!
   
    Thank you!

John