Automatic balancing circuit for longitudinal transmission system
AssigneeThe Inteleplex Corporation
InventorsJohn M. Sues, Jing H. Sun
Life of this patent
Estimating the term…
Abstract
Transmission and reception of first and second information signals over a telephone local loop, simultaneous with voice communications over the same local loop, is possible if the phase and amplitude of said first and second signals are perfectly balanced. The inventive apparatus detects differences in phase and amplitude between said first and second signals, and generates digital control signals to reduce the phase and amplitude differences to zero. Adjustment of phase and amplitude is completely automatic and rapidly accomplished.
Claims9
Apparatus for balancing the phase and amplitude of first and second signals transmitted and received over a telephone local loop, said first signal being coupled between a ring conductor and earth ground, and said second signal being coupled between a tip conductor and earth ground, said apparatus comprising:
- first means for detecting a difference in amplitude between said first and second signals,
- second means for detecting a difference in phase between said first and second signals,
- programmable digital processing means, responsive to said first amplitude difference detecting means and said second phase difference detecting means, for generating digital control signals indicative of the difference in phase and amplitude between said first and second signals,
- first means responsive to said control signals for equalizing the amplitude of said first and second signals, and
- second means responsive to said control signals for equalizing the phase of said first and second signals.
Dependencies are inferred from the claim text.