“signal in handset”… it’s not very clear. What do you mean ? The RXLEV DL ?
If it goes down suddenly, then go up again:
– bad power control settings
– strong fast fading (urban areas, lots of reflections)
– hardware problem: the ericsson BTS is having trouble in generating the Tx Power
– cable problems / connectors: it’s possible the cable is a bit loose, there is water, or too much bending?