available until the Block III satellites are deployed. Like the other new GPS signals, M-code is dependent on OCX — specifically Block 2 — which was scheduled to enter service in October 2016, but which has been delayed until 2022, and that initial date did not reflect the two year first satellite launch delay expected by the GAO. Other M-code characteristics are: Satellites will transmit two distinct signals from two antennas: one for whole Earth coverage, one in a spot beam. Binary offset carrier modulation. Occupies 24 MHz of bandwidth. It uses a new MNAV navigational message, which is packetized instead of framed, allowing for flexible data payloads. There are four effective data channels; different data can be sent on each frequency and on each antenna. It can include FEC and error detection. The spot beam is ~20 dB more powerful than the whole Earth coverage beam. M-code signal at Earth's surface: –158 dBW for whole Earth antenna, –138 dBW for spot beam antennas. Safety of Life (L5) Safety of Life is a civilian-use signal, broadcast on the L5 frequency (1176.45 MHz). In 2009, a WAAS satellite sent the initial L5 signal test transmissions. SVN-62, the first GPS block IIF satellite, continuously broadcast the L5 signal starting on 28 June 2010. As a result of schedule delays to the GPS III control segment, the L5 signal was decoupled from the OCX deployment schedule. All satellites capable of transmitting the L5 signal (all GPS satellites launched since May 2010) began broadcasting pre-operational civil navigation (CNAV) messages in April 2014, and in December 2014 the Air Force started transmitting CNAV uploads on a daily basis. The L5 signal will be considered fully operational once at least 24 space vehicles are broadcasting the signal, currently projected to happen in 2024. As of 2 February 2022, L5 was being broadcast from 16 satellites, up from 12 in February 2020. Improves signal structure for enhanced performance. Higher transmission power than L1 or L2C signal (~3 dB, or twice as powerful). Wider bandwidth, yielding a 10-times processing gain. Longer spreading codes (10 times longer than used on the C/A code). Located in the Aeronautical Radionavigation Services band, a frequency band that is available worldwide. WRC-2000 added space signal component to this aeronautical band so the aviation community can manage interference to L5 more effectively than L2. It is defined in IS-GPS-705. New civilian L1 (L1C) L1C