CYBLE-224110 Transmit power with MTK carrier wave test mode

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jechc_4023571
Level 1
Level 1

Hi,

I'm having trouble getting the right output power with the test firmware from KBA220073 in continuous wave mode.

Executing "TXP 15 0 1500" gives me pulses that I measure close enough to 0dBm.

But with "TXC 15 0", the measured power is much lower, around -35dBm.

I can vary the power from -18dBm to +3dBm, but in both cases with "TXC" the measured power is always 35dBm lower.

Any ideas?  Could it have something to do with the external power amplifier control lines not being correctly toggled in the continuous carrier wave mode?

Thanks.

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1 Solution
GuhapriyanT_31
Employee
Employee
10 solutions authored 25 replies posted 10 replies posted

Hi Jerome,

The TXC command is implemented by bypassing the Link Layer & controlling the radio directly. The PA/LNA controls are done by the Link Layer hardware. So, in this case, the PA/LNA controls are not active resulting in the power loss. The solution to this is to put the PA control lines in GPIO mode and enabling the PA lines through firmware when starting this command and putting back to DDFT/LL control while exiting this mode.

Thanks,

Guha

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2 Replies
GuhapriyanT_31
Employee
Employee
10 solutions authored 25 replies posted 10 replies posted

Hi Jerome,

The TXC command is implemented by bypassing the Link Layer & controlling the radio directly. The PA/LNA controls are done by the Link Layer hardware. So, in this case, the PA/LNA controls are not active resulting in the power loss. The solution to this is to put the PA control lines in GPIO mode and enabling the PA lines through firmware when starting this command and putting back to DDFT/LL control while exiting this mode.

Thanks,

Guha

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Hello Guha,

Thanks a lot. I did exactly as you suggested and got it working.

Regards,

Jerome

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