Fedora 15: Netgear WG111v2 menjadi sangat lambat setelah waktu singkat

Di bawah Fedora 15, adaptor Netgear WG111v2 (USB) saya terhubung dengan baik ke AP saya, memungkinkan kecepatan pengunduhan normal sekitar 800 kbps selama sekitar 20 detik dan kemudian turun menjadi sekitar 100 kbps. Apa penyebabnya dan bagaimana saya bisa mengubahnya menjadi perilaku normal? Tingkat 800kbps normal di Windows. Menariknya, ada beberapa output cfg80211 di dmesg (lihat di bawah).

Output dari iwconfig wlan0:

wlan0     IEEE 802.11bg  ESSID:"xxx"  
      Mode:Managed  Frequency:2.457 GHz  Access Point: xx:xx:xx:xx:xx:xx   
      Bit Rate=54 Mb/s   Tx-Power=20 dBm   
      Retry  long limit:7   RTS thr:off   Fragment thr:off
      Power Management:off
      Link Quality=48/70  Signal level=-62 dBm  
      Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
      Tx excessive retries:0  Invalid misc:74139   Missed beacon:0

dmesg:

[19860.248887] cfg80211: World regulatory domain updated:
[19860.248890] cfg80211:     (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
[19860.248893] cfg80211:     (2402000 KHz - 2472000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
[19860.248895] cfg80211:     (2457000 KHz - 2482000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
[19860.248897] cfg80211:     (2474000 KHz - 2494000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
[19860.248899] cfg80211:     (5170000 KHz - 5250000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
[19860.248901] cfg80211:     (5735000 KHz - 5835000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
[19860.248911] cfg80211: Calling CRDA for country: AT
[19860.252536] cfg80211: Regulatory domain changed to country: AT
[19860.252539] cfg80211:     (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
[19860.252543] cfg80211:     (2402000 KHz - 2482000 KHz @ 40000 KHz), (N/A, 2000 mBm)
[19860.252545] cfg80211:     (5170000 KHz - 5250000 KHz @ 40000 KHz), (N/A, 2000 mBm)
[19860.252548] cfg80211:     (5250000 KHz - 5330000 KHz @ 40000 KHz), (N/A, 2000 mBm)
[19860.252551] cfg80211:     (5490000 KHz - 5710000 KHz @ 40000 KHz), (N/A, 2700 mBm)
[19861.857688] wlan0: authenticate with xx:xx:xx:xx:xx:xx (try 1)
[19861.859561] wlan0: authenticated
[19861.967688] wlan0: associate with xx:xx:xx:xx:xx:xx  (try 1)
[19861.969696] wlan0: RX ReassocResp from xx:xx:xx:xx:xx:xx  (capab=0x431 status=0 aid=2)
[19861.969699] wlan0: associated

Biasanya ini memperlambat adalah bahwa daya adaptor nirkabel Tx Anda terlalu tinggi. AP kemudian menolak sensitivitas Rx dan Anda menyadarinya sebagai perlambatan.