Control System Objects with Multiple Streams of Information D. Kucherov Computerized Control System National Aviation University Kyiv, Ukraine d_kucherov@ukr.net A. Kozub Usage of Space Systems and GIS Software Department National University of Defence of Ukraine Kyiv, Ukraine kozubtanja@rambler.ru Abstract – The article deals with the problem of controlling the flow of information coming from a group of UAVs by radio channel. The stream is a sequence of binary information packages. The inevitable data losses are compensated by repetition of lost packages. Modern methods control of data flow assumes using a mechanism ARQ based on the method sliding window. In this paper the comparative analyses of the known methods are given. The property matching the volume of information, which is transmitted from UAVs with the size M of the sliding window, is set. In base of theoretical calculations is used the concept of bandwidth. Computing bandwidth radio channel with the ARQ technology allows are confirming the main result investigation. Keywords – flow data; probability error; automatic repetition query (ARQ); stop and wait scheme; throughput I. INTRODUCTION Today the number of researchers takes attention to the collective management of unmanned machines based on radio remote control. It is the task of executing the works with the risk to human life, the need to perform tasks in a limited time, a long time carry out routine work. Application tasks of collective control include search and monitoring operations, extinguishing fires in large areas of the earth's surface and other [1, 2]. When controlling the actions of the group UAVs need to transfer large amounts of information on the ground control station. Information is transmitted package that simplifies the information processing. The movement of aircraft, equipment malfunctions, there is interference on radio propagation path, some data packets may be lost or, for example, there may be no confirmation of it receipt. Some authors propose technologies actions planning networks of UAVs, which based on discipline scheduling, i.e. the order of processing of the transmitted packages [3-10]. However, an important task becomes developing algorithms compensate for lost packets. A natural approach to solving this problem is to re-send lost packets to the point of reception and processing of information. Stop and wait mode for re-packages is estimated as inefficient way to retrieve lost packets. In this case, the channel is long time stopped before receiving the series of packages. More promising is the use of window, which slides over the flow of information. If we repeat the lost information in a fixed window, it is possible to improve radio channel using. In practice the selective rejection mode also gives analogical of using channel [11]. The problem, which is studied in this paper, is to compare these technologies in terms of preference and obtaining estimates of the size for sliding window. In this paper discusses the problem of estimating the load of the transmission channel in the presence of loss of data on the basis of these methods. II. PROBLEM STATEMENT Let have a group from n UAVs, which gives information to operator's remote control by radio link. Operator determined for UAVs path, active zone, control and correction routes. Operator and UAV exchange this information as usually by packages. The package is a certain amount of binary information, organized in a certain way that named protocol. All UAVs transmits information to the ground control station in an asynchronous mode, then processing system for input stream has the form n UAV UAV UAV I I I I     ... 2 1 , (1) where i UAV I  the data flow from i of source and n i , 1  . Here the problems of auto identification, authentication don’t solving. The packages from all UAVs are considered as whole one stream. The main problem in this transferring data is motion UAVs, mismatch processing speeds in reception and transmission points, buffer overload is due to data retrieval on a low speed, retransmission data to another address, and errors during transmission data. Consequently, it becomes necessary to control the flow of data. There are some methods to control the flow of data. Among them stop and wait, return to the M steps, selective rejection. The last two approaches are known as a mechanism