A summary of the new GPS IIR-M and IIF modernization signals

This paper discusses the planned modernization of the block IIR-M and IIF GPS satellite signals, including the addition of the new military signal. In particular a brief review of the legacy signals is presented, followed by a description of the new military signal, the M code signal (with its data and data-less components). Next the new civil signal which is the replacement C/A code for L2, is discussed. Interplex combining is then presented. Interplex modulation combines three signals and provides a constant envelope to the power amplifier by producing an intermodulation term. Finally, the new L5 civilian signal is elucidated.