Wikipedia
Single Channel Ground and Airborne Radio System (SINCGARS) is a Combat Net Radio (CNR) currently used by U.S. and allied military forces. The radios, which handle voice and data communications, are designed to be reliable, secure, and easily maintained. Vehicle-mount, backpack, airborne, and handheld form factors are available.
SINCGARS uses 25 kHz channels in the very high frequency (VHF) FM band, from 30 to 87.975 Megahertz (MHz). It has single-frequency and frequency hopping modes. The frequency-hopping mode hops 111 times a second.
The SINCGARS family has mostly replaced the Vietnam-war-era synthesized single frequency radios ( AN/PRC-77 and AN/VRC-12), although it can work with them. The airborne AN/ARC-201 radio is phasing out the older tactical air-to-ground radios (AN/ARC-114 and AN/ARC-131).
Over 570,000 radios have been purchased. There have been several system improvement programs, including the Integrated Communications Security (ICOM) models, which have provided integrated voice and data encryption, the Special Improvement Program (SIP) models, which add additional data modes, and the advanced SIP (ASIP) models, which are less than half the size and weight of ICOM and SIP models and provided enhanced FEC ( forward error correction) data modes, RS-232 asynchronous data, Packet Data formats, and direct interfacing to Precision Lightweight GPS Receiver (PLGR) devices providing radio level situational awareness capability.
In 1992, the U.S. Air Force awarded a contract to replace the AN/ARC-188 for communications between Air Force aircraft and Army units.