Method for removing bias in a frequency hopping digital communication system
First Claim
1. In a frequency hopping digital communications system having a transmitter for transmitting a data signal via a noisy transmission path, and a receiver responsive to said transmitted signal for receiving the same, a method for removing bias in said data signal at said receiver comprising the steps of:
- forming a sample amplitude histogram from said received data signal samples for a given hop frequency;
correlating said amplitude histogram against a stored reference amplitude histogram to obtain a correlated output signal having a peak correlation position;
determining the position difference between said peak correlation position and a correlation center position to provide an offset signal corresponding to said difference and indicative of an estimated bias offset value;
applying said estimated bias offset value to said received signal samples in response to said offset signal to obtain an output signal indicative of an unbiased received data signal.
2 Assignments
0 Petitions
Accused Products
Abstract
There is disclosed in a frequency hopping digital communications system having a transmitter for transmitting a data signal via a noisy transmission path, and a receiver responsive to the transmitted signal for receiving the same, a method for removing bias in the data signal at the receiver comprising the steps of: forming a sample amplitude histogram from the received data signal samples for a given hop frequency; correlating the amplitude histogram against a stored reference amplitude histogram to obtain a correlated output signal having a peak correlation position; determining the position difference between the peak correlation position and the correlation center position to provide an offset signal corresponding to the difference and indicative of an estimated bias offset value; and applying the estimated bias offset value to the received signal samples in response to the offset signal to obtain an output signal indicative of an unbiased received data signal.
-
Citations
20 Claims
-
1. In a frequency hopping digital communications system having a transmitter for transmitting a data signal via a noisy transmission path, and a receiver responsive to said transmitted signal for receiving the same, a method for removing bias in said data signal at said receiver comprising the steps of:
-
forming a sample amplitude histogram from said received data signal samples for a given hop frequency; correlating said amplitude histogram against a stored reference amplitude histogram to obtain a correlated output signal having a peak correlation position; determining the position difference between said peak correlation position and a correlation center position to provide an offset signal corresponding to said difference and indicative of an estimated bias offset value; applying said estimated bias offset value to said received signal samples in response to said offset signal to obtain an output signal indicative of an unbiased received data signal. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
-
-
11. In a frequency hopping digital communications system having a transmitter for transmitting a data signal via a noisy transmission path, and a receiver responsive to said transmitted signal for receiving the same, an apparatus for removing bias in said data signal at said receiver comprising:
-
amplitude means for forming a sample amplitude histogram from said received data signal samples for a given hop frequency; reference means for forming a reference amplitude histogram indicative of an ideal sample amplitude histogram; correlation means responsive to said amplitude means and to said reference means for correlating said amplitude histogram against said reference amplitude histogram to obtain a correlated output signal having a peak correlation position; means for determining the position difference between said peak correlation position and a correlation center position to provide an offset signal corresponding to said difference and indicative of an estimated bias offset value; application means responsive to said offset signal for applying said estimated bias offset value to said received signal samples to obtain an output signal indicative of an unbiased transmitted data signal. - View Dependent Claims (12, 13, 14, 15, 16, 17, 18, 19, 20)
-
Specification