ELS61-E antenna test | Telit Cinterion IoT Developer Community
July 25, 2017 - 11:57am, 3307 views
We have developed a modem PCB with the ELS61-E module and two U.FL antenna connectors (one for the main and one for the RX diversity antenna).
What is the best way to test these two antenna connections.
Which AT-command should I use and what should be the response of that AT-Command?
Hello,
there is no easy way to check antenna RF path - you must have for RX Signal Generator and for TX Signal Meter.
You can make general judge by checking AT^SMONI command and verify signal parameters Srxlev,RSRP,RSRQ like below in Idle state:
SrxlevRX level value for base station selection in dB (see 3GPP 25.304)RSRPReference Signal Received Power (see 3GPP 36.214 Section 5.1.1.)RSRQ
Reference Signal Received Quality (see 3GPP 36.214 Section 5.1.2.)
^SMONI: ACT,EARFCN,Band,DL bandwidth,UL bandwidth,Mode,MCC,MNC,TAC,Global Cell ID,Physical Cell ID,Srxlev,RSRP,RSRQ,Conn_state
^SMONI: 4G,6300,20,10,10,FDD,262,02,BF75,0345103,350,33,-94,-7,NOCONN
Best regards
Lukasz
Hi,
we have a similar problem (in our case a PLS8-e) but I think the question is independent of the model. So I append to this thread.
In production test we connect one antenna to our board (the antenna interfaces are routed from the PLS8-E pads to MCX sockets). We want to check if the antenna RF paths are connected correctly. No SIM card inserted. To check both antenna paths we think it is neccessary to connect only one at a time and repeat the test for the 2nd antenna socket.
First we limit the band to LTE800 with the command at^scfg=Radio/Band,2097152,1 to force the module into the 4G MIMO mode (can be undone with at^scfg=Radio/Band,2928787,1). In this band and at our location the module usually connects to the vodafone network (MCC,MNC = 262,02). RSRP is usually about -87dB. This can be checked with at^smoni. If the RSRP is worse than -90dB then the board has failed.
But some modules (about 15%) decide to use the telefonica network (MCC,MNC = 262,03) which has a RSRP of -115dB. We have to modify our test software to accept alternatively this network with RSRP not worse than -118dB. Or we must insert a vodafone SIM to get always this network. Both solutions are not very comfortable.
Is there a way to force the module without SIM card to a particular network and to 4G mode? Or even better to a particular base station? (at+cops works only with SIM)
Is there a test/measurement mode in these modules (in our case a PLS8-e) to check the RF path with a simple non-modulated RF signal? We think testing only one direction from module to measurement equipment or from signal generator to module would be sufficient. We are confident that transmitter and receiver of the module itselft are tested enough at the Gemalto factory.
Or is it better to use a base station simulator? But we think these are usually build for certification testing and are very expensive. We don't want to do a compliance test of the module but just only a connection test of our board. Can you recommend a simple base station simulation?
Regards
Hendrik
In between I opened a new thread because I think my question will not be found in this old thread.
https://iot-developer.thalesgroup.com/threads/antenna-test