I'm trying to properly setup an HM-TRP FSK radio module to send and receive data the best it can at 56kbps.

I think I'm wrong with setting it up to use 600Khz "receive bandwidth" and 160Khz "modulate deviation" (I'm taking the quoted text from the HM-TRP datasheet).

When I look online, I see a formula like this:

Bandwidth = data rate + (2 times frequency deviation)

When I look in the datasheet, I see this:

Modulation index: h = Fd/Rb, Range is 0.5 - 32.
If h > 1, BW = Rb + 2Fd; If h < 1, BW = 2Rb + Fd

For the module defaults, they use:

Data rate: 9.6 Kbps
Receive Bandwidth: 105 Khz
Modulate Deviation: 35 Khz

Because the datasheet says nothing more about the Rb, Fd, and BW variables, I'm going to assume it means Receiving Bytes, Frequency Deviation (Modulate Deviation) and Bandwidth respectively.

The datasheet can be found here: http://www.hoperf.com/upload/rf/HM-TRP.pdf

Given all this, how do I configure the "Modulate Deviation" and "Receive Bandwidth" for a 56Kbps data rate?


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