HL78 radio output power

IoT Modules HL78
1

Hy,

For our testing, we use channel emulator.
But our channel emulator accept maximum input power at +15 dBm and the HL78 can go to +23dBM.

Is there a command to limit the HL78 to +15 dBM ?

Thanks

2

Hi philippe.surbayrole,

Please take a look at the command +WMTXPOWER in HL78xx AT Commands Interface Guide document.

Thanks,

3

Hi Jerdung,

I know the command +WMT POWER, but it’s for “Test RF Tx” as mentioning in Sierra AT commands documentation.
Not for limiting the TX power in common use.

4

Hi philippe.surbayrole,

The HL78xx module’s LTE maximum transmitter output power for all bands in normal operation conditions (25°C) is specified in Table 4-23 page 59 of HL78xx Product Technical Specification document. You cannot limit TX power in HL78xx products.

If possible, please disable the restriction of maximum input power on your emulator side.

Thanks,

5

@philippe.surbayrole

So to answer your question in a bit more detail and to allay your concerns.

All 3GPP UE’s operate with active power control where EnodeB will command a unit to transmit more or less as it likes to receive all signals at the same level regardless of whether they are next to it or 20km away. The maximum possible transmit power of the HL78 is +23dBm but only if the EnodeB tells it to transmit that hard. As a result and as Jerdung said, you need to make sure you emulator does not command the unit to to this and it will not.

Regards

Matt