Results of continued testing:
WAP54g access point with latest Linksys software
WRT54g v2 client in infra mode at 8 km distance with parabolic antennas and amplifiers. S/N ratio > 30 dB. Gmode only (2).
software: HEAD (7-8-2005) compilation with modified wificonf.c to be able to experiment with settings.
problem: excessive frame errors and limitation of effective data rate to ~ 700 kbps even though indicated bit rate ('wl rate') is much higher.
frameburst and gmode protection have no significant influence on bit rate.
the client automatically reduces its bitrate to 2 Mbps for least bad result.
Have used same client WRT54Gv2 but now with WRT54Gv2.2 access point with same HEAD based firmware. Just 1 meter apart and no amplifiers or special antennas.
Observation: when doing file transfers, using openssh sftp server, from client to AP the data rate saturates at some 1.5 Mbps, even though gmode bitrate is 54 Mbps on both sides and does now not reduce. S/N ratio > 50 dB. Used 6 MB file to be sent back and forth. Once per ~10 transfers the AP box hangs up and resets itself.
'Ifconfig eth1' shows very high frame error numbers on both sides.
I think that there is a problem around these frame errors. Perhaps they don't really exist but are just the result of some software interface error but they do upset the box as with plenty of data to be sent and received it cannot cope with a massive amount of retransmissions and associated bookkeeping and intermediate storage of data.
Anybody reading this that is familiar with frame error checking in the radio link and its interface to Busybox ?
Another strange thing is that after booting the box and without yet having had any contact to another box 'ifconfig eth1' shows 0 data transfer but already does show a number of frame errors, as if it is freely generating them by itself.
(Last edited by doddel on 15 Aug 2005, 12:39)