How to increase carrier bandwidth?

[Ted]

Hi friend,

I use SDK16.0, and the version of softdevice is S140 V7.0.1. We have a project using the nrf52840, which is sometimes used by carriers. I ported radio_test to my project and disabled the BLE stack when only the carrier is needed. We need to increase the RF transmit power to 19dbm. So we added a Skyworks RFX2411 amplifier to boost the RF power. Now the FCC requires that if the RX transmission power reaches 19dbm, the carrier bandwidth must be greater than 500KHz. Currently I use radio_unmodulated_tx_carrier(RADIO_TXPOWER_TXPOWER_Pos8dBm, RADIO_MODE_MODE_Nrf_1Mbit, 40) to generate the carrier and use the timer interrupt to generate 1Kbps OOK data I want to send. How to increase bandwidth? 

Best wishes

Ted Wu

[Asbjørn]

Hello Ted,

you have to use the modulated carrier option on radio test to create a carrier with wider bandwidth. 

Best regards

Asbjørn

[Ted]

Hi Asbjørn,

Thank you for your reply. When I change the function from radio_unmodulated_tx_carrier to radio_modulated_tx_carrier the system locks up at the rnd8 function. Please see the picture below. I want to use 2.4GHz RF OOK 500 bps Manchester encoding. How to set transmit_pattern_t? Is g_pattern set to TRANSMIT_PATTERN_RANDOM, TRANSMIT_PATTERN_11001100, TRANSMIT_PATTERN_11110000 or something else?

Best wishes

Ted Wu