US 12,283,932 B2
Method, system and storage medium of proportional-integral-derivative based automatic gain control for satellite transponder system under partial-time partial-band additive white gaussian noise jamming
Yajie Bao, Germantown, MD (US); Peng Cheng, Germantown, MD (US); Khanh Pham, Kirtland AFB, NM (US); Erik Blasch, Arlington, VA (US); Dan Shen, Germantown, MD (US); Xin Tian, Germantown, MD (US); and Genshe Chen, Germantown, MD (US)
Assigned to Intelligent Fusion Technology, Inc., Germantown, MD (US)
Filed by Intelligent Fusion Technology, Inc., Germantown, MD (US)
Filed on Sep. 15, 2023, as Appl. No. 18/467,808.
Prior Publication US 2025/0096761 A1, Mar. 20, 2025
Int. Cl. H03G 3/30 (2006.01)
CPC H03G 3/3068 (2013.01) [H03G 3/3078 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A method of proportional-integral-derivative (PID) based automatic gain control (AGC) for a satellite transponder system under partial-time partial-band additive white Gaussian noise (AWGN) jamming, comprising:
receiving a sequence of sample signals by a AGC processor after an analog-digital-converter (ADC) in the satellite transponder system;
determining two different block sizes from the sequence of sample signals wherein a block size of a first block of sample signals is greater than a block size of a second block of sample signals;
using the block size of the first block to compute a first signal-amplitude-ratio (SAR)-based gain value and using the block size of the second block to compute a second signal-amplitude-ratio (SAR)-based gain value by the AGC processor through the sequence of sample signals; and
if the first SAR-based gain value is greater than an amplitude threshold, calculating a to-be-applied gain control value of an m-th transmitted symbol at a n-th time step, m and n are non-zero positive integers, using the second SAR-based gain value, a tracking error at a (n−1)-th time step, a summation of a plurality of tracking errors from a 1-st time step to the (n−1)-th time step, and a tracking error difference between the tracking error at the (n−1)-th time step and a tracking error at a (n−2)-th time step; or
if the first SAR-based gain value is equal to or less than the amplitude threshold, calculating a to-be-applied gain control value of an m-th transmitted symbol at a n-th time step using a minimum difference between an estimated amplitude and each of reference amplitudes in a lookup table (LUT), and the tracking error difference between the tracking error at a (n−1)-th time step and the tracking error at a (n−2)-th time step.