@Julia Chavez yeah, 1-2km in a semi-open field is well within the module's comfortable range, so throughput degradation shouldn't be your main concern at that distance — you're nowhere near the edge of the link budget.
The 2Mbps is the PHY rate, but you're right that it's a best-case figure. At that distance with typical ground-level multipath you'll see some overhead from retransmits and protocol framing, but for your use case it honestly doesn't matter much. Accelerometer + baro + GPS coords at 20Hz is a pretty light payload — you're probably looking at a few KB/s actual data throughput, which the link handles comfortably even with headroom to spare.
On the PHY rate question — the module doesn't do automatic rate adaptation the way WiFi does. It's not going to silently drop to 1Mbps or 500K coded PHY on its own as RSSI degrades. If you want to manually configure a lower data rate (which gives you better sensitivity and more robust link at the cost of throughput), you can do that through the firmware configuration, and honestly for a 20Hz telemetry stream at 1-2km you'd barely notice the throughput difference but your link margin would improve noticeably. Worth considering if you're operating near terrain or vegetation that might create more attenuation than a clean open field.
The AI Firmware Builder in the Dev Hub is actually pretty useful for this — you can describe your telemetry setup and it'll generate configuration code with the PHY settings exposed so you can experiment without starting from scratch.
