$Logfile = "WifiLog.txt"
Function LogWrite
{
   Param ([string]$logstring)
   write-host $logstring
   Add-content $Logfile -value $logstring
}

LogWrite "Timestamp,Connected,SSID,BSSID,Channel,Signal,Receive,Transmit"
While($true)
{
    $NetSH = netsh wlan sh int | Select-String State,bssid,signal,Channel,SSID,"Receive rate","Transmit rate"
    $a = $NetSh -split(" : ")
    $output = $(Get-Date -Format G)+","+$a[1]+","+$a[3]+","+$a[5]+","+$a[7]+","+$a[9]+","+$a[11]+","+$a[13]
    LogWrite $output
    Start-Sleep 10
}