Description
The VERTEX 7134 ANTENNA CONTROLLER System developed by Vertex Communications Corporation, is a microprocessor-based system incorporating advanced technology for accurate antenna positioning with high reliability, maximum flexibility, and a straightforward and practical user interface. This control system is ideally suited for small and medium aperture antenna applications requiring capabilities for automatic multiple satellite access, program track, remote control via an RS-232 or RS-422 communications link, and optional automatic step track operation.
The optional Vertex Adaptive Step Track (AST) algorithm performs the function of conventional step track peak signal level optimization but without the random “guessing” errors associated with predetermined fixed scan patterns. AST s AZ and EL peaking operations upon a mathematical relationship relating the change in received signal level to a given change in angular position. For each axis, an
initial fixed size step is taken, and signal strength levels before and after the step are used to determine the magnitude and direction of the corrective (peaking) step required. Once the peak position is determined, flags are set, indicating the direction of travel of the space-craft so that the initial step for the next peaking operation will tend to move the antenna along the satellite ephemeris. This feature greatly reduces the errors introduced by the “wrong” guess made during significant portions of the daily satellite drift by algorithms which consistently make initial steps in a given direction.
The standard product is provided as a 2-speed system for AZ and EL with a high/low speed ratio of up to 15:1. This is accomplished by application of user-settable high- and low-speed control signals to variable speed AC drives, which in turn control standard 3-phase induction motors. For 3-axis systems, circuitry is provided for the control of an AC synchronous stepping polarization motor. The AZ and EL motor controllers employ integral electronic protection, and the drive cabinet includes NEMA-rated circuit protection devices for each motor/motor controller, sized appropriately for each application. The drive cabinet housing is foot-mounted and comes standard as a NEMA 4X-rated (stainless steel or aluminum) enclosure for outstanding corrosion protection even in the harshest of environments.