This special issue of the International Journal of Microwave and Wireless Technologies is dedicated to topics discussed at the National Conference on Reconnaissance Systems and Electronic Warfare, held from 21 to 23 October 2016 in the picturesque village of Oltarzew, near Warsaw, Poland. The conference, organized jointly by the Institute of Telecommunications and the Institute of Radioelectronics of the Military University of Technology, welcomed more than 120 attendees. The conference was chaired by Professor Jerzy Lopatka and co-chaired by Professor Piotr Kaniewski. The three-day event was accompanied by an industrial exhibition where 18 companies presented their recent achievements in the area of electronic reconnaissance and EW.

This special issue of the International Journal of Microwave and Wireless Technologies, published by Cambridge University Press in collaboration with EuMA, covers three topics selected from more than 49 presented papers. The authors were requested to submit their papers, and almost 20 international reviewers agreed to review the English versions of the submitted papers.

Finally, the three best papers were selected for publication in this special issue.

The first paper presents problems related to the optimization of a wireless sensor network for electromagnetic situation monitoring. The paper deals with the difficult problem of monitoring the electromagnetic spectrum in an urban environment. The second paper deals with the problem of designing absorbers for outdoor measurement. The authors present an idea for the outdoor measurement of the impact of high energy pulses (HEP) on different equipment, and they use a specially developed absorber to protect other devices and decrease multipath effects during measurements.

The third paper present the idea of radio bearing measurements of sources with directional antennas in an urban environment, especially in non-line-of-sight conditions.

We hope that this special issue devoted to electronic reconnaissance and warfare, a subject which appears only occasionally in open literature, will be enjoyable and of interest to the readers through various topics in the microwave field, and that they will also find extensive and useful information for their own research activities