Which angle refers to GPS signal reliability being affected by atmospheric conditions?

The mask angle is indeed the correct choice when discussing the impact of atmospheric conditions on GPS signal reliability. The mask angle refers to the minimum angle relative to the horizon at which satellite signals are considered usable. When signals are received from satellites that are located closer to the horizon, they must pass through a greater volume of the Earth's atmosphere. This increased atmospheric interference can lead to errors in the GPS signal, as dense atmospheric layers and weather conditions can degrade signal quality.

In surveying and GPS applications, it's crucial to use an appropriate mask angle to filter out low-elevation satellites that may not provide reliable data due to atmospheric disturbances. By setting a higher mask angle, surveyors can ensure that the satellites being used for positioning are higher in the sky, which typically provides clearer signals and better accuracy.

The other angles mentioned, such as the reception angle, elevation angle, and exposure angle, do not specifically address the reliability of signals as affected by atmospheric conditions in the context of GPS technology. The reception angle relates more to how well a satellite's signal can be received, the elevation angle pertains to the angle of a satellite above the observer's horizon without necessarily factoring in the atmospheric influence, and the exposure angle generally refers to the exposure of a receiver to satellite signals without direct