The Swedish Defence Research Agency (FOI) has published a 132-page introduction to electromagnetic warfare. It is intended as training material within Sweden’s total defence. The report, released in October, covers electromagnetic warfare against radio communications, radar, electro-optical and laser communication systems. It uses NATO’s division into support, attack and protective measures.
The publication opens with an example from nature. A bat hunts using ultrasonic echolocation and can detect prey about five metres away. A moth can hear the bat’s calls from about 40 metres, which FOI compares to a radar warning receiver. Some moths also click to jam the bat’s sonar.
FOI states that jamming of satellite navigation signals is common far outside war zones. According to the report, jamming aimed at civilian activity occurs in Sweden and its neighbouring region. FOI calls this “an active example of hybrid warfare.” The interference has also been noted in the Baltic Sea, which FOI says can endanger civil shipping and aviation.
The report also highlights software-defined radio, which makes spoofing open satellite signals relatively easy. The same technology is cutting the cost of anti-jamming protection. Military systems of this kind can cost 50 times more than the receiver they protect. FOI notes that cheaper protection also makes precision weapons harder to counter with electromagnetic warfare.
The report is the latest in FOI’s “FOI informerar om” series. It follows a guide on nuclear weapons published in September, previously reported by NDS.