What feature contributes to the greater positional accuracy of survey grade GPS receivers compared to recreational models?

The greater positional accuracy of survey-grade GPS receivers is primarily attributed to their ability to utilize dual-frequency and multiple channel tracking. This advanced technology allows these receivers to process signals from multiple satellites simultaneously and operate on both L1 and L2 frequencies. By doing so, they can correct for errors caused by atmospheric conditions, such as delays in the ionosphere, which can significantly impact accuracy.

In contrast, recreational models generally rely on single-frequency tracking and may limit the number of satellites they can utilize, leading to increased susceptibility to these types of errors, thus compromising positional accuracy. Survey-grade receivers, with their enhanced capabilities, can achieve centimeter-level accuracy, making them essential for precise applications such as land surveying and construction projects.