The problem of time in phased array radar

A concern associated with phased array radar has been that of not being able to “get round the sky quick enough”, in other words that the time taken to look in all beam positions is likely to be unacceptably long. A number of factors contribute to this problem: (a) relatively long dwells dictated by the need for clutter suppression, (b) the demands on the time of other functions, principally tracking, (c) arrays containing large numbers (many thousands) of elements and (d) large solid angles of search, for example a rotating array. We examine the question of long search times and attempt to quantify `unacceptably long´, with surprising results. We also look at the trade-off between search time and power. In addition we investigate the use of interlaced scans with increased beam position separations to give an alternative means of reducing the search load