6dB band width of IF filter

[Kiyoshi Egawa]

Hello, we are using a radio module with the nRF51822 for our telemetry system.

In order to conduct the EMC test of EN 301 489-1, I would like to clarify the 6dB bandwidth of IF filter, because the spurious responses at 349MHz and its harmonic frequencies are not so good.

According to the EN 301 489-1(4.4: Narrow band responses of receivers or receivers which are part of transceivers), we can evaluate the EMC test at the frequency of the test signal which is increased by an amount equal to twice the nominal 6 dB bandwidth of the IF filter, if there are spurious response issues at related to the IF band.

Could you disclose the 6dB bandwidth of IF filter to us?

Thanks in advance.

[FormerMember]

In 1 Mbps mode, the 6 dB bandwidth is 1.4 MHz.

In 2 Mbps mode, the 6 dB bandwidth is 3 MHz.

[Kiyoshi Egawa]

Hello,

Thanks for your prompt response.

We are normaly using nRF51822 in 2Mbps mode.

If possible, could you share the frequency characteristic of the IF filter in 2Mbps mode with me, because we would like to have it as an evidense for our technical document?

Thanks for your understanding and cooperation.