We consider the problem of MIMO channel estimation subject to a given error and delay constraints. Our objective is to minimize the energy spent during the channel estimation phase, which includes transmission of training symbols, storage of those symbols at the receiver, and also channel estimation at the receiver. We develop a model that is independent of the hardware or software used for channel estimation, and use a divide and conquer strategy to minimize the overall energy consumption.

Emerging technologies in communications and information processing are having, and will continue to have, a significant effect on the way command and control (C2) is carried out on the battlefield of the future. One of these technologies is a packet-switched, internetwork, computer-communications system. This system concept allows for the interconnection of heterogeneous computers on heterogeneous networks, thereby providing for rapid, efficient, and reliable communications between processing elements-regardless of their physical location. This type of telecommunications architecture also allows automatic network reconfiguration when switching nodes or communications links fail. This permits system survivability in stressed environments. This communications system provides the means for passing time-critical information in a reliable and efficient fashion for purposes of C2. To achieve survivable C2, however, it is also necessary to integrate distributed software and data-processing technology with this telecommunications architecture technology. To achieve a survivable and effective C2capability, an experimental distributed command, control, and communications C3architecture has been evolved that blends these evolving communications and processing technologies with innovative concepts in tactical battle management. A joint Army/Defense Advanced Research Projects Agency (DARPA) Testbed, located at Fort Bragg, North Carolina, is being established to explore survivable C3concepts based on this architecture. This testbed, supported under the Army/DARPA Distributed Communications and Processing Experiment (ADDCOMPE), was started in late 1984. The ADDCOMPE testbed is leveraging the results of the earlier Army Data Distribution (ADDS) testbed also situated at Fort Bragg. However, ADDS primarily addressed communications; the ADDCOMPE program's emphasis is not only on communications but also on distributedprocessing environments (software and hardware) and distributed C2applications implemented over such an environment. In ADDCOMPE, the ADDS communications architecture is being taken as "available" technology but is being extended to include packet-switched, internetwork communications implemented over present-day Army communications systems. In this paper, an overview of the ADDCOMPE telecommunications architecture is presented and a discussion of the general philosophy for use of the ADDCOMPE testbed to support technology transfer to the Army is given. As this architecture is implemented, future papers will discuss its technical details, such as protocols used, throughput delay characteristics, and the like. Future papers will also provide technical discussions on the distributed-processing software (system and C2applications) developed for the testbed.

In this paper we present a new methodology for designing reliable communication protocols. This methodology enhances communicating processes with a synchronization mechanism so that they can detect and resolve the errors caused by collisions automatically. The major advantages of this new methodology include: (1) the “state explosion” problem involved in protocol validation is alleviated; and (2) the burden of handling errors due to collisions is removed from the protocol designer. There is a need to verify that this methodology is applicable to arbitrary protocols. In this paper we also discuss the application of a program verification technique to this methodology.