Methodology and computer tools to semi-automate assessments of shortwave broadcast coverage resulting from multiple transmissions

A computer-assisted methodology, developed for using a point-to-point ionospheric propagation and communications system performance model to assess shortwave broadcast coverage, is presented. The listening area is approximated by a set of geographic coordinates (test points), and the required power gain (RPRG) for the link from each transmitter site to each test point is computed using the IONCAP ionospheric communications analysis and prediction program. The broadcasts may originate simultaneously from a single site or from multiple-transmitter sites (i.e., multicast). Figures of merit are assigned in terms of the RPG values, and area coverage statistics are computed for the simulated broadcasts. Three interactive computer programs were developed to permit a semi-automated multicast broadcast coverage analysis using IONCAP and a computerized equipment database. They are: propagation parameter set-up program; transmission plan set-up program; and multicast analysis program.