Simulation of a distributed system for performance modelling

Abstract

A distributed system of cooperating minicomputers is simulated by AIMER (Automatic Integration of Multiple Element Radars) to model and analyze the behavior of a radar tracking system. Simulation is applied in the AIMER project in an attempt to model a network of minicomputers to discover a maximally flexible network architecture. Because building the tracking system out of real hardware would not result in a flexible enough testbed system, the proposed configuration is represented by a software emulation. The instruction sets of the individual processors are emulated in order to allow separation of the measurement facilities from the execution of the system. The emulation is supported by a Nano-data QM-1 micro and nano-programmable host. Extensive performance monitoring hooks have been built into the emulation system which allow small performance perturbations to become visible. The tracking network is controlled by a combination firmware operating system and a special emulated virtual control machine. The tracking algorithms run on virtual machines whose instruction sets and computational throughput can be parameterized when the model is generated, or dynamically by an operator during a run. The radar and ground truth environments for the tracking system are simulated with logic resident in one of the emulated machines, allowing these functions to be monitored as accurately as the tracking algorithms. The use of this simulation technique has resulted in an extremely flexible testbed for the development of distributed radar tracking system models. The testbed itself can be quickly tailored to other application problems.