the elements of a conventional costas loop an input line 14 receives an input signal consisting of a carrier signal and a plurality of time sequential data signals the data signals include a code signal or code word that identifies the beginning of each data signal and is used to determine bit timing and data timing as will be hereinafter described in more detail the input signal received at input line 14 is applied to an in phase mixer 16 and a quadrature phase mixer 18 a local voltage controlled oscillator 20 generates a local oscillator signal that is applied directly to the quadrature phase mixer 18 and is multiplied therein by the input signal the local oscillator signal is also applied through a 90 u00b0 phase shifter 22 to the in phase mixer 16 where the 90 u00b0 phase shifted local oscillator signal is multiplied by the input signal the output of the in phase mixer 16 is applied to a low pass filter 24 and likewise the output of the quadrature phase mixer 18 is applied to a low pass filter 26 when the local oscillator signal of the voltage controlled oscillator 20 is synchronized with the carrier signal component of the input signal the carrier signal is removed by the in phase mixer 16 so that the output signal of the low pass filter 24 is demodulated base band data the signal path following the in phase mixer 16 is commonly referred to as the i channel and the signal path following.