Practical use of space interference

MALD is a state-of-the-art, low-cost expendable flight vehicle that is modular, air-launched and programmable. It weighs fewer than 300 pounds and has a range of approximately 500 nautical miles. MALD-J adds radar-jamming capability to the basic MALD platform.

Experts are starting to delve into how well the Global Positioning System (GPS) satellite navigation network resists the effects of electronic jammer– intentional or accidental. The emerging answer is not very well.

The 4G jammer affecting GNSS can be intentional and unintentional ones. Intentional jammers include deceiving jammers and suppressing jammers, of which the suppression jammers are dominant, and they suppress the navigation signals by emitting high power signals, such as broadband, narrowband or continuous wave (CW) . Therefore, this paper focuses on the reduction of the suppressing jamming signals.

Generally, an antenna array for interference suppression is a spatial filter. It is a signal- processing method which makes use of the spatial selectivity of antenna array to filter out the jammers and to improve the SNR. The anti-jamming algorithms based on antenna array are divided into two categories according to their goals. One is the Digital Beam Forming (DBF), which adjusts the main beam automatically to the desired signals. The other is the Adaptive Nulling algorithm], which points the nulls to cell phone jammer. The DBF requires the direction information of GNSS signals and its computation is quite complex. As a result, its jamming mitigation performance will degrade severely if errors of the estimation on GNSS signals’ direction increase.

The news of the spy plane’s GPS troubles comes on the heels of rumors that North Korea is working on a new (or souping up an old) jammer. South Korean officials have claimed that Kim’s jammers had a range of between 50-100 kilometers. But a South Korean Defense Ministry report on Tuesday indicated that the North is at work on a jammer with a range of more than 100 km.

The second was a spinoff of the Russian system manufactured domestically in North Korea, which is believed to have similar capabilities but costs less on the open market. South Korean intelligence has claimed that in early 2010, North Korea purchased a new 24-Watt jammer from Russia – capable of jamming GPS reception within a 400 kilometer radius, which basically covers the entire Korean Peninsula.