In accordance with the appointment, in every system there are two basic frequencies – L1 (Standard definition) and L2 (high precision). For navstar L1 = 1575,42 MHz and L2 = 1227,6 MHz. In glohass uses frequency separation of signals, ie, each satellite operates at its own frequency and, accordingly, L1 is in the range from 1602.56 to 1615.5 MHz and L2 from 1246.43 to 1256.53. Signal in the L1 is available to all users, the signal in the L2 – only the military (ie, can not be decrypted without the express private key). Each satellite system, in addition to basic information, reports and supporting, necessary for continuous operation receiving equipment. This category includes a complete anthology of all the satellite constellation, the transmitted sequence in a few minutes.
Thus, the start of the reception device can be fast enough if it contains the actual almanac (about 1 minute) – this is called "warm start", but may take up to 15 minutes, if the receiver has to receive a full almanac – Sc. "Cold Start. The need for a "cold start" usually occurs when you first turn on the receiver, or if he has not been used. On the differences between systems, said on 22/6/2007 Internet briefing the press service of the Federal Space Agency Director General – Designer General, Research and Production Association of Applied Mechanics (NPO pm, , Krasnoyarsk Territory) Nicholas Testoedov. Nicholas Testoedov: 'Comparison of systems that designed around the same time – in 80 years of the last century shows that they are close to destination, output characteristics, the potential accuracy of the location, structure, logic operation and management.