wireless interface not recognized on boot

My network connection has been pretty stable; but after a few days up and running, I start to notice hints of connection issues. I get knocked offline, or at any rate cannot connect, but I only notice when a web page won't load or Kmail gives me an error message. (I don't get a notification that I am now offline.) I can usually reconnect, though sometimes I notice what seem to be lingering ghosts of dead connections, with my old IP address(es), even though I've killed all my previous connections. After I reconnect, I can use email, surf the web, whatever, but these issues tend to increase, and my connection seems unstable, though I cannot tell why. When at last I reboot my system, the startup shell invariably tells me that my wireless connection (wlan0) is not recognized, although eth0 is okay. I have managed to get my wireless connection back by booting with a live Debian or Devuan disc, where my wireless connection is always available. Then I reboot into my Devuan system, and usually my wireless connection is again recognized and available; it used to be that this trick always worked, but now it only works sometimes. My connection issues also used to get worse over time; then I would reinstall my system, and everything would be fine once more, and only deteriorate over several weeks or so. But now I've reinstalled my system a couple times, and these wireless issues seem to be constant, even on a fresh installation. A direct connection is not possible; wireless internet service is available to tenants in my building (although I'm sure that, by now, in my neighborhood, everybody's dog has cracked our insecure password). And while this is a desktop computer that I'm using, I get wireless by using a wifi antenna, which has served me reliably for years. Another interesting detail: I tried using an old Kubuntu 8.04 Hardy Heron live CD to boot the computer, and it also did not recognize my wireless connection; so I wonder if this is not a TDE bug, rather than a problem with the Devuan system. I haven't tried booting into other desktops yet, but I suppose I could install some other DEs and compare. I've already tried every command-line solution I could think of: ifup / ifdown iwconfig wlan0 txpower on and so on. Sorry for the long post, but I wanted to include whatever details might be significant. Any suggestions for how to resolve these issues (other than by reinstalling yet again) would be most appreciated. Bill