Synchronous receiver
First Claim
1. A synchronous receiver including:
- means for receiving a carrier signal comprising a phase-shift modulated signal with binary data having a baud rate;
carrier recovery means providing a recovered carrier signal;
absolute phase comparison means providing an absolute phase output signal related to said binary data and measured by the phase difference between the received phase-shift modulated signal and said recovered carrier signal, comprising;
a multiple sample means providing a plurality of sampled absolute phase signals; and
sample average means providing said absolute phase output according to an average of said sampled absolute phase signals.
2 Assignments
0 Petitions
Accused Products
Abstract
A synchronous receiver for receiving a phase shift modulated signal having binary data at a clock rate occurring within a baud interval. The synchronous receiver provides multiple estimates of the signal phase during selected portions of the baud interval, wherein the resulting phase values are averaged to provide a data output of low error rate and high reliability. The synchronous receiver of the present invention independently recovers the carrier and clock signals by separate digital phase-locked loops, wherein the resulting signals are used by the synchronous detector portion to recover the digital data. Moreover, the data acquisition time is improved by variable bandwidth characteristics of the phase locked loops.
28 Citations
21 Claims
-
1. A synchronous receiver including:
-
means for receiving a carrier signal comprising a phase-shift modulated signal with binary data having a baud rate; carrier recovery means providing a recovered carrier signal; absolute phase comparison means providing an absolute phase output signal related to said binary data and measured by the phase difference between the received phase-shift modulated signal and said recovered carrier signal, comprising; a multiple sample means providing a plurality of sampled absolute phase signals; and sample average means providing said absolute phase output according to an average of said sampled absolute phase signals. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18)
-
-
19. A self-adjusting wave forming means receiving an analog signal having a periodicity and forming a digital received signal having the same periodicity as said analog signal, said wave forming means comprising:
-
amplifier means having an inverting and non-inverting input and an output providing said digital received signal; reference voltage means corresponding to a voltage at the mid-point of the amplifier output; a first resistor connected to said amplifier output and said non-inverting input; a second resistor connected to said non-inverting input and said reference voltage means; a third resistor connected to said amplifier output and said inverting input; and a capacitor connected to said inverting input and said analog signal wherein the product of the values of the third resistor and the capacitor are substantially greater than the period of the analog signal.
-
-
20. A method of detecting data signals in a digitally modulated carrier, comprising the steps of:
-
multiple data sampling the signal over a sample period corresponding to the open area of the eye pattern to sychronously detect said data signals; averagaing the data sample over the sample period; recovering a carrier signal; and phase-locking said recovered carrier signal over a period corresponding to the open area of the eye pattern. - View Dependent Claims (21)
-
Specification