Synchronous rectification track circuit
First Claim
1. A synchronous detection track circuit system comprising, a stretch of continuous railway track having a plurality of block sections, each defined by a transmitter coupled to one end and a code-responsive receiver coupled to the other end;
- one of said plurality of block sections includes a transmitter having a first carrier frequency signal which is modulated by code signals having one phase angle and includes a code-responsive receiver;
another adjacent one of said plurality of block sections includes a transmitter having a second carrier frequency signal which is modulated by code signals having said one phase angle and also includes a code-responsive receiver;
a next adjacent one of said plurality of block sections includes a transmitter having said first carrier frequency signal which is modulated by code signals having another phase angle which is displaced 90°
from said one phase angle and includes a code-responsive receiver;
a following adjacent one of said plurality of block sections includes a transmitter having said second carrier frequency signal which is modulated by code signals having said another phase angle and includes a code-responsive receiver;
a subsequent adjacent one of said plurality of block sections includes a transmitter having said first carrier frequency signal which is modulated by code signals having said one phase angle and includes a code-responsive receiver;
a next succeeding adjacent one of said plurality of block sections includes a transmitter having said second carrier frequency signal which is modulated by code signals having said one phase angle and includes a code-responsive receiver.
2 Assignments
0 Petitions
Accused Products
Abstract
An improved audio frequency track circuit system utilizes a synchronous train detection arrangement and reduces the number of fixed code rate modulated carrier signals. As few as two carrier signals are alternately applied at discrete points along a pair of jointless track rails to define the transmitter ends of the track sections, with complementary receivers defining the opposite ends. The two carrier signals are coded at one of two phase angles which are 90° out-of-phase so that, when assigned, the nearest possible interfering signal is 90° out-of-phase and is rejected thereby. Like carrier frequency transmitter/receiver arrangements are disposed on opposite sides of an insulated joint but are coded 180° out-of-phase so that a breakdown of the insulated joint is detected and the false code signal is rejected.
33 Citations
19 Claims
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1. A synchronous detection track circuit system comprising, a stretch of continuous railway track having a plurality of block sections, each defined by a transmitter coupled to one end and a code-responsive receiver coupled to the other end;
- one of said plurality of block sections includes a transmitter having a first carrier frequency signal which is modulated by code signals having one phase angle and includes a code-responsive receiver;
another adjacent one of said plurality of block sections includes a transmitter having a second carrier frequency signal which is modulated by code signals having said one phase angle and also includes a code-responsive receiver;
a next adjacent one of said plurality of block sections includes a transmitter having said first carrier frequency signal which is modulated by code signals having another phase angle which is displaced 90°
from said one phase angle and includes a code-responsive receiver;
a following adjacent one of said plurality of block sections includes a transmitter having said second carrier frequency signal which is modulated by code signals having said another phase angle and includes a code-responsive receiver;
a subsequent adjacent one of said plurality of block sections includes a transmitter having said first carrier frequency signal which is modulated by code signals having said one phase angle and includes a code-responsive receiver;
a next succeeding adjacent one of said plurality of block sections includes a transmitter having said second carrier frequency signal which is modulated by code signals having said one phase angle and includes a code-responsive receiver. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
- one of said plurality of block sections includes a transmitter having a first carrier frequency signal which is modulated by code signals having one phase angle and includes a code-responsive receiver;
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12. A synchronous detection track circuit system comprising a stretch of continuous railway track having a plurality of block sections, each defined by a transmitter coupled to one end and a code-responsive receiver coupled to the other end;
- one of said plurality of block sections includes a transmitter having a first carrier frequency signal which is modulated by code signals having one phase angle and includes a code-responsive receiver;
another adjacent one of said plurality of block sections includes a transmitter having a second carrier frequency signal which is modulated by code signals having said one phase angle and also includes a code-responisve receiver;
a next adjacent one of said plurality of block sections includes a transmitter having said first carrier frequency signal which is modulated by code signals having another phase angle which is displaced 90°
from said one phase angle and includes a code-responsive receiver;
a following adjacent one of said plurality of block sections includes a transmitter having said second carrier frequency signal which is modulated by code signals having said another phase angle and includes a code-responsive receiver;
a subsequent adjacent one of said plurality of block sections includes a transmitter having said first carrier frequency signal which is modulated by code signals having said one phase angle and includes a code-responsive receiver;
a next succeeding adjacent one of said p1urality of block sections includes a transmitter having said second carrier frequency signal which is modulated by code signals having said one phase angle;
a next succeeding portion of said stretch of continuous railway track having insulated joints;
an adjacent code-responsive receiver coupled to the track rails on the other side of the insulated joints and responsive to a coded carrier signal having said second carrier frequency signal which is modulated by code signals having a phase angle which is 180°
out-of-phase with said one phase angle so that a deteriorating insulated joint will result in cancellation of said coded carrier signal of said adjacent code-responsive receiver. - View Dependent Claims (13, 14, 15, 16, 17, 18, 19)
- one of said plurality of block sections includes a transmitter having a first carrier frequency signal which is modulated by code signals having one phase angle and includes a code-responsive receiver;
Specification