Antenna arrays are now an established technology for radar and communication equipment. However, the links between the different techniques are often not recognized. Processing of array data is done digitally as close to the element as possible. This has created a realm of possibilities of building array hardware structures and of multichannel processing schemes. Examples are not only many algorithms of nonlinear wave parameter estimation and adaptive interference suppression, but also array configurations with sparse arrays and various types of subarrays. These configurations constitute special solutions of a hardware compromise between analog and digital processing. Furthermore, we have methods involving higher order statistics and methods of compressed sensing, which both lead to virtual arrays of larger size and potentially better resolution properties. Additionally, there can be combinations of spatial and temporal processing (in particular space-time adaptive processing, STAP).

The purpose of this special issue is to bring together these antenna and processing related aspects, linking the theoretical possibilities with the operational aspects and hardware constraints. Potential topics include:

• Array pattern synthesis and sidelobe reduction
• Adaptive interference suppression, sidelobe blanking
• Slow- and fast-time STAP
• Direction finding, monopulse, and superresolution methods
• Array configurations and subarray concepts
• Array processing for MIMO, passive radar, and ECM/ESM sensors
• Emerging techniques and innovative concepts

Before submission authors should carefully read over the journal's Author Guidelines, which are located at http://www.hindawi.com/journals/ijap/guidelines/. Prospective authors should submit an electronic copy of their complete manuscript through the journal Manuscript Tracking System at http://mts.hindawi.com/submit/journals/ijap/radar/ according to the following timetable: