On Thu, Dec 02, 2010 at 09:58:23PM +0300, Sergey V. Efimoff wrote:
But right after the very first GSM call the receive level quickly jumps down to -70 or even -80 dBm, this value corresponds to 30mW of output power. BTS station still works and output power is still shown as 2W.
In case you are running a multi-TRX BTS: is this the received power level on the TCH of the call or on the BCCH ? If downlink power control is active, the BTS will not send more power than needed on a dedicated channel...
This effect had been discovered with only one of my BTS stations, while other stations work well. Does it mean that it's a hardware problem? Has anyone discovered this problem earlier?
Are the other BTS's configured exactly the same way? As explained, the difference single-trx / dual-trx and downlink power control might explain it.
otherwise, if configuration of bs-11, openbsc and the bs11 firmware is identical, it might well be a hardware issue. But I don't get why it would be related to the first call or not...
Regards, Harald