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SX1262 Freq selection hardware consideration

Hey All

The SX1262… the radio range in the datasheet cover from 100 to 1000 mhz roughly. All available devices seem to be centered frequently on 433, 868 or 915.

I know there is a hardware and optimization aspect to have different frequency selected but other then that. What stops me from building a simple module that does an okay job any software selected freq even if not optimized for a specific band. And what is the compromise in terms of Sensitivity ? Radiated power ? 10% ? 50%?

Thanx

I dont know what the effect on sensitivity would be.

What are the plans to correctly match the RF ouput of the SX126X to the antenna across such a wide range of frequencies ?

And how would you supress unwanted harmonics, so the end device can be certified, across such a wide range of frequencies ?

Hi Stuart, valid questions, at this stage is purely research and maybe prototyping, I had the same concerns about the matching and even the antenna selection todo an okay job at all freq and I suspect the same will count for impedance control " okay job" I found alot of 50/50 Balun thats claim less then 1db insertion from 200 to 1000mhz so I suppose this is the best wideband approach.

As far as Harmonics go. -TBA The existance of SDR radios with 3 or 4 Ghz span just tells me that this cant be completly out of reach.

The radio would have be recalibrated when swithcing bands aswell as reinitialize between swithcing and some Radiated power is expected to be lost. but im wondering the same percentage would be sacrificed in SNR and sensitivity.

The performance at a fundamental frequency outside the intended range would depend on (1) the insertion loss of your matching circuit (directly measurable), (2) the impedance seen by the transceiver pins, which have some optimal impedance, and (3) the PA settings which can be optimized for current consumption, output power, and harmonics.

But this sounds like an interesting exercise, finding the sensitivity outside of the intended operating range for a fixed reference design BOM, then seeing if the BOM can be tailored to accommodate a wider operating range with a tradeoff in performance.