and 90s with the introduction of low-cost and highly portable laser designators. A laser beam can be made much narrower than a radar beam while not increasing the size of the broadcaster. Additionally, it is simple to encode additional information in the beam using digital means, which has a number of advantages. Missiles with small optical receivers on their tail can beam-ride on lasers with similar ease as earlier radar beam systems, but will be inherently more accurate. Additionally, as the beam is very narrow by design, less power is needed than a semi-active design where the volume of space being "painted" is generally larger, in order to ensure the missile body does not block all of the signal. This makes it more difficult to be noticed by the target's warning receiver. Very low power signals can be used. In modern use, laser beam riding is generally limited to short-range missiles, both anti-air and anti-tank. Examples include ADATS, the Starstreak, the RBS 70, MSS-1.2, Russian 9K121 Vikhr and 9M119 Svir, Ukrainian Skif and Stuhna-P ATGMs. References External links Jerzy Maryniak et al., "Modeling of Motion of an Automatically Controlled Beam-Riding Guided Missile in Terms of the Maggi Equations" (pdf), AIAA Atmospheric Flight Mechanics Conference and Exhibit, August 2005 Missile Guidance, aerospaceweb.org, accessed March 14, 2007 Greg Goebel, "Early Radar Technology", February 1, 2007, accessed March 14, 2007 Carlo Kopp, "Man Portable Surface-Air Missiles", Australian Aviation, July, 1989 Carlo Kopp, "Active and SemiActive Radar Missile Guidance", Australian Aviation, June 1982 Missile guidance Military radars Military lasers