In recently, GPS technique has become a powerful positioning and navigation tool. However, there are still some drawbacks to GPS, such as the view of sky obstructed, causing the positioning accuracy degraded. The pseudolite, a satellite-like GPS ground signal generator, is then expected to provide extra-measurements and improve the GPS accuracy, coverage, and availability at the obstructed areas. It has been preliminarily proved by this study that the operation of GPS pseudolite can improve the repeatability of vertical component from 2 cm to 1 cm. It is encouraged that a level of 50% improvement can even be achieved at a test area without any obstruction to the view of sky. There is potential to practically upgrade the GPS effectiveness, especially for cadastral surveys carried on urban canyon, by using GPS pseudolite.