The Development board CC1120EMK has the following features
- MSP430F5438 MCU
- USB interface
- 128 x 64 dot matrix LCD
- 3 axis digital accelerometer
- Ambient light sensor
We did a theoretical range estimation using the RF Range Estimator Tool from TI
Link: https://www.ti.com/tool/RF-RANGE-ESTIMATOR
This tool is very simple, but much powerful in estimating a near practical value. The tool supports the selection of different terrain, Receiver Transmitter antenna height, fine-tuning of Environment Noise Floor (NF) level, conducted output power value etc.
Given below is the Range estimation we got from the tool.
According to this tool, we will get three different range estimations
Friss (LOS) - This is the maximum attainable range when the Radio waves do not hit the Earth Ground which can attenuate the radiated signals. This type of testing can be done only if the Receiver and Transmitter are placed on a mountain top or high altitude so that radio waves do not hit the Ground Floor during the propagation
Without Interference: This value corresponds to the practical value which we will be getting as the range between the CC1120 Transmitter and Receiver if we test this on a levelled surface ( eg: Sea coast, highways ) without any objects acting as interference in the propagation path. This can be thought of as the outdoor range of the CC1120 module
With Interference: This value corresponds to the range obtained indoors with the Concrete Slab, Glass door etc on the path. TI's RF Range Estimator tool has many options under "Absorbtion Material" selection to get an estimated range in indoor testing.
With the values we obtained from the tool in mind, we did testing in "Without Interference" condition.
We did the testing in Varkala Beach in Trivandrum, where we were able to get about 1 kilometer of straight sight. We geotagged the receiver which was placed at a height of about 5 meter and moved the transmitter away from the receiver.
Following are the test details.
| Test Method | From TI RF Range estimator Tool | Without Interference ( Varkala Beach ) |
| Range( Rx - 1m, Tx 1m) | 773 meters | about 750 meters |
| Range( Rx - 5m, Tx 1m) | 1220 meters | about 1100 meters |
The result which is shown in the Range estimator tool matched with our practical test result.
We are working on developing a board with CC1120 with CC1190 RF Frontend. We will be discussing the details of further testing in the coming days.
Stay tuned