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The MBS system has been tested extensively in various urban/suburban environments in the San Francisco Bay Area and proved to be best in class in several blind independent tests held by the Communications Security, Reliability, Interoperability Council (CSRIC), an advisory body to the Federal Communications Commission (FCC), and by the Cellular Telecommunications and Internet Association (CTIA)/Alliance For Telecommunications Industry Solutions (ATIS).

Figure 39.21 Representative 2D accuracy walk test result.

A sample 2D performance walk test result from a mall in the San Francisco Bay Area is shown in Figure 39.21 using only MBS signals. The results are shown in ENU coordinates with the x‐ and y‐axis representing the east and north displacement in meters. The red markers indicate the position truth and the blue circle markers indicate the position estimates using MBS measurements only. The results show sub‐10‐m 2D error performance.

A sample z‐axis test result from a hotel in the San Francisco Bay Area is shown in Figure 39.22. The truth position is shown in dashed red lines, and the MBS estimated altitude is shown in black. The results show altitude estimates within a floor throughout this test.

A sample result from an outdoor drive test in a small campus‐wide MBS network is shown in Figure 39.23. The black path shows the position truth path, and the blue path colors show the estimated position from the MBS. In this test, position estimates are computed using the MBS beacon measurements only. The results show that the 2D error was less that 10 m a majority of the time.