When considering an operational GNSS such as a GPS system, it is easy to assume that testing a receiver involves connecting it to an antenna and putting it in an outside environment, and checking whether the receiver can locate and navigate on the received GNSS signals.
This assumption can be acceptable to some extent. This method of verifying the antenna is known as live sky testing and is useful in checking the processing circuits and assuring that the receiver’s radio frequency is functional. The GPS constellation simulator’s hardware can be a good alternative.
Nevertheless, when you need to test a GPS enabled device it is more than checking for operation ability, and you cannot rely on live sky testing. Also, live sky testing is not reliable when you test a product’s life cycle that begins with conception and ends with integration.
But how do you perform a simulator test?
The process of setting up a test on a GPS receiver is quite straight forward. This process is in two stages:
The Definition Stage
At this juncture, a simulator control software is essential for setting up required test parameters. You need to understand the receiver applications and the environment. After you have determined the tests you need to carry out, you can determine the test scenario. Lastly, you need to know how you will connect the receiver to maintain the optimum RF conditions.
Run-time is the final stage where the scenario is in running mode. The GPS constellation simulator’s hardware produces requisite RF signals. You should observe the receiver’s performance while manipulating the simulator appropriately. You can then go ahead and analyze the performance of the receiver.
In comparison to using real signals, GPS constellation simulators are a better alternative for testing purposes. You get full control of simulated environmental conditions and simulated satellite signals. Also, testers can generate different kinds of tests while using a GPS simulator.