Claims
- 1. Apparatus for testing return signals in an electrical or optical communications medium, the apparatus comprising:
- a timing control circuit producing a sequence {.sup..phi. k}.sub.k of pulse clock signals at successive clock cycles;
- a word generator for receiving the sequence of pulse clock signals and for generating and issuing a set of four code sequences {r.sup.m.sub.k }.sub.k (m=1,2,3,4), two of which may be identical, for each pulse clock signal k, where the code sequence values r.sup.m.sub.k are all non-negative or all non-positive and are determined by the relationships
- r.sup.1.sub.k =b.sup.L.sub.k +G.sup.1.sub.k,
- r.sup.2.sub.k =b.sup.L.sub.k +G.sup.2.sub.k,
- r.sup.3.sub.k =r.sup.4.sub.k =b.sup.L.sub.k,
- where the two sequences {G.sup.m.sub.k }.sub.k (m=1,2) form a Golay pair of complementary code sequences of length L that satisfy the relation ##EQU16## where L is an integer greater than one, where .delta..sub.ik is the Kronecker delta symbol, and where {b.sup.L.sub.k }hd k is a sequence having L consecutive terms equal to one or to a fixed non-zero constant value, with all other terms of the sequence being zero, the word generator further generating and issuing two correlation sequences {c.sup.m.sub.k }.sub.k (m=1,2,3,4) defined by
- c.sup.1.sub.k =c.sup.3.sub.k =G.sup.1.sub.k,
- c.sup.2.sub.k =c.sup.4.sub.k =G.sup.2.sub.k ;
- injection means for receiving the pulse clock signal sequence {.phi..sub.k }.sub.k, for receiving a signal sequence {r.sup.m.sub.k }.sub.k from the word generator, and for injecting this sequence in successive clock cycles k into the communications medium;
- detection means for receiving the pulse clock signal {.phi..sub.k }.sub.k and for detecting a return signal sequence {x.sup.m.sub.k }.sub.k produced by the communications medium in successive clock cycles k in response to injection of the signal sequence {r.sup.m.sub.k }.sub.k for each integer m=1,2,3,4; and
- processing means for receiving the pulse clock signal sequence {.phi..sub.k }.sub.k, for receiving the return signal sequence {x.sup.m.sub.k }.sub.k in successive clock cycles k, and for forming a linear combination z.sub.k of the four return signal sequences ##EQU17## where the sequence {z.sub.k }.sub.k represents the return signal for a pulse input signal injected into the communication medium.
- 2. Apparatus for testing return signals in an electrical or optical communications medium, the apparatus comprising:
- a timing control circuit producing a sequence {.phi..sub.k }.sub.k of pulse clock signals at successive clock cycles;
- a word generator for receiving the sequence of pulse clock signals and for generating and issuing a set of 2M code sequences {r.sup.m.sub.k }.sub.k (m=1,2, . . . , 2M) for each pulse clock signal k, where the code sequence values r.sup.m.sub.k are all non-negative or all non-positive and are determined by the relationships
- r.sup.m.sub.k =b.sup.L.sub.k +G.sup.m.sub.k (m=1,2,3,4),
- where the two sequences {G.sup.m.sub.k }.sub.k (m=1,2) from a first Golay pair of complementary code sequences of length L that satisfy the relation ##EQU18## where the two sequences {G.sup.m.sub.k }.sub.k (m=3,4) form a second Golay pair of complementary code sequences of length L that satisfy the relation ##EQU19## where the four Golay code sequences {G.sup.m.sub.k }.sub.k (m=1,2,3,4) satisfy the relation ##EQU20## where L is an integer greater than one, .delta..sub.ik is the Kronecker delta symbol, and {b.sup.L.sub.k }.sub.k is a sequence having L consecutive terms equal to one or to a fixed non-zero constant value, with all other terms of this sequence being zero, the word generator further generating and issuing for correlation sequences {c.sup.m.sub.k {.sub.k (m,2,3,4) defined by
- c.sup.1.sub.k =G.sup.1.sub.k -G.sup.2.sub.k =-c.sup.2.sub.k,
- c.sup.3.sub.k =G.sup.3.sub.k -G.sup.4.sub.k =-c.sup.4.sub.k ;
- injection means for receiving the pulse clock signal sequence {.phi..sub.k }.sub.k, for receiving a signal sequence {r.sup.m.sub.k }.sub.k from the word generator, and for injecting this sequence in successive clock cycles k into the communications medium;
- detection means for receiving the pulse clock signal {.phi..sub.k }.sub.k and for detecting a return signal sequence {x.sup.m.sub.k }.sub.k produced by the communications medium in successive clock cycles k in response to injection of the signal sequence {r.sup.m.sub.k }.sub.k for each integer m=1,2,3,4; and
- processing means for receiving the pulse clock signal sequence {.phi..sub.k }.sub.k, for receiving the return signal sequence {x.sup.m.sub.k }.sub.k in successive clock cycles k, and for forming a linear combination z.sub.k of the four return signal sequences ##EQU21## where the sequence {z.sub.k }.sub.k represents the return signal for a pulse input signal injected into the communications medium.
- 3. Apparatus for testing return signals in an electrical or optical communications medium, the apparatus comprising:
- a timing control circuit producing a sequence {.phi..sub.k }.sub.k of pulse clock signals;
- a word generator for receiving the sequence of pulse clock signals and for generating and issuing a set of four code sequences {.sup.n r.sup.m.sub.k }.sub.k (m=1,2,3,4) for each pulse clock signal k for a fixed integer n.gtoreq.0, where the code sequence values .sup.n r.sup.m.sub.k are all non-negative or all non-positive and are determined by the relationships
- .sup.n r.sup.1.sub.k =b.sup.L.sub.k +.sup.n G.sup.1.sub.k,
- .sup.n r.sup.2.sub.k =b.sup.L.sub.k -.sup.n G.sup.1.sub.k,
- .sup.n r.sup.3.sub.k =b.sup.L.sub.k +.sup.n G.sup.2.sub.k,
- .sup.n r.sup.4.sub.k =b.sup.L.sub.k -.sup.n G.sup.2.sub.k,
- where L=2.sup.n for a positive integer n, where {b.sup.L.sub.k }.sub.k is a sequence having L consecutive terms equal to one or to a fixed non-zero constant value, with all other values of the sequence being zero, where {.sup.n G.sup.1.sub.k }.sub.k and {.sup.n G.sup.2.sub.k }.sub.k form a Golay pair of complementary code sequences of length L that satisfy the relation ##EQU22## where .delta..sub.ik is the Kronecker delta, and where the Golay pair of code sequences {.sup.n+1 G.sup.1.sub.k }.sub.k and {.sup.n+1 G.sup.2.sub.k }.sub.k for an integer n+1.gtoreq.1, are generated inductively by the relationships
- .sup. G.sup.1.sub.k ={1},
- .sup.0 G.sup.2.sub.k ={1},
- .sup.n+1 G.sup.1.sub.k ={.sup.n G.sup.1.sub.k, .sup.n G.sup.2.sub.k }, (n.gtoreq.0)
- .sup.n+1 G.sup.1.sub.k ={.sup.n G.sup.1.sub.k, -.sup.n G.sup.2.sub.k }, (n.gtoreq.0)
- the word generator further generating and issuing a correlation sequence {.sup.n c.sup.m.sub.k }.sub.k of length L=2.sup.n corresponding to each sequence {.sup.n r.sup.m.sub.k }.sub.k (m=1,2,3,4) and being defined by
- .sup.n c.sup.1.sub.k =.sup.n G.sup.1.sub.k =-.sup.n c.sup.2.sub.k,
- .sup.n c.sup.3.sub.k =.sup.n G.sup.2.sub.k =--.sup.n c.sup.4.sub.k ;
- injection means for receiving the pulse clock signal sequence {.phi..sub.k }.sub.k, for receiving a signal sequence {.sup.n r.sup.m.sub.k }.sub.k from the word generator, and for injecting this sequence in successive clock cycles k into the communications medium;
- detection means for receiving the pulse clock signal {.phi..sub.k }.sub.k and for detecting a return signal sequence {.sup.n x.sup.m.sub.k }.sub.k produced by the communications medium in successive clock cycles k in response to injection of the signal sequence {.sup.n r.sup.m.sub.k }.sub.k for each integer m=1,2,3,4; and
- processing means for receiving the pulse clock signal sequence {.phi..sub.k }.sub.k, for receiving the return signal sequence {.sup.n x.sup.m.sub.k }.sub.k in successive clock cycles k, and for forming a linear combination .sup.n z.sub.k of the four return signal sequences defined by ##EQU23## where the sequence {.sup.n z.sub.k }.sub.k represents the return signal for a pulse input signal injected into the communications medium.
- 4. Apparatus for testing return signals in an electrical or optical communications medium, the apparatus comprising:
- a timing control circuit producing a sequence {.phi..sub.k }.sub.k of pulse clock signals;
- a word generator for receiving the sequence of pulse clock signals and for generating and issuing a set of four code sequences {.sup.n r.sup.m.sub.k }.sub.k (m=1,2,3,4) for each pulse clock signal k for a fixed integer n.gtoreq.0, where the code sequence values .sup.n r.sup.m.sub.k are all non-negative or all non-positive and are determined by the relationships
- .sup.n r.sup.1.sub.k =b.sup.L.sub.k +.sup.n G.sup.1.sub.k,
- .sup.n r.sup.2.sub.k =b.sup.L.sub.k -.sup.n G.sup.1.sub.k,
- .sup.n r.sup.3.sub.k =b.sup.L.sub.k +.sup.n G.sup.2.sub.k,
- .sup.n r.sup.4.sub.k =b.sup.L.sub.k -.sup.n G.sup.2.sub.k,
- where L=2.sup.n for a positive integer n, where {b.sup.L.sub.k }.sub.k is a sequence having L consecutive terms equal to one or to a fixed non-zero constant value with all other values of the sequence being zero, where {.sup.n G.sup.1.sub.k }.sub.k and {.sup.n G.sup.2.sub.k }.sub.k form a Golay pair of complementary code sequences of length L that satisfy the relation ##EQU24## where .delta..sub.ik s the Kronecker delta, and where the Golay pair of code sequences {.sup.n+1 G.sup.1.sub.k }.sub.k and {.sup.n+1 G.sup.2.sub.k }.sub.k for an integer n+1.gtoreq.1, are generated inductively by the relationships
- .sup. G.sup.1.sub.k ={1},
- .sup.0 G.sup.2.sub.k ={1},
- .sup.n+1 G.sup.1.sub.k ={.sup.n G.sup.1.sub.k, .sup.n G.sup.2.sub.k }, (n.gtoreq.0)
- .sup.n+1 G.sup.1.sub.k ={-.sup.n G.sup.1.sub.k, .sup.n G.sup.2.sub.k }, (n.gtoreq.0)
- the word generator further generating and issuing a correlation sequence {.sup.n c.sup.m.sub.k }.sub.k of length L=2.sup.n corresponding to each sequence {.sup.n r.sup.m.sub.k }.sub.k (m=1,2,3,4) and being defined by
- .sup.n c.sup.1.sub.k =.sup.n G.sup.1.sub.k =-.sup.n c.sup.2.sub.k,
- .sup.n c.sup.3.sub.k =.sup.n G.sup.2.sub.k =-.sup.n c.sup.4.sub.k ;
- injection means for receiving the pulse clock signal sequence {.phi..sub.k }.sub.k, for receiving a signal sequence {.sup.n r.sup.m.sub.k }.sub.k from the word generator, and for injecting this sequence in successive clock cycles k into the communications medium;
- detection means for receiving the pulse clock signal {.phi..sub.k }.sub.k and for detecting s return signal sequence {.sup.n x.sup.m.sub.k }.sub.k produced by the communications medium in successive clock cycles k in response to injection of the signal sequence {.sup.n r.sup.m.sub.k }.sub.k for each integer m+1,2,3,4; and
- processing means for receiving the pulse clock signal sequence {.phi..sub.k }.sub.k, for receiving the return signal sequence {.sup.n x.sup.m.sub.k }.sub.k in successive clock cycles k, and for forming a linear combination .sup.n z.sub.k of the four return signal sequences defined by ##EQU25## where the sequence {.sup.n z.sub.k }.sub.k represents the return signal for a pulse input signal injected into the communications medium.
CROSS REFERENCE TO RELATED APPLICATION
This application is a continuation of application Ser. No. 07,139, filed 02/06/89, now abandoned, which is a continuation of application Ser. No. 935,661, filed 11/26/86, now abandoned.
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
4743753 |
Cheng et al. |
May 1988 |
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Foreign Referenced Citations (1)
Number |
Date |
Country |
0060337 |
Apr 1984 |
JPX |
Continuations (2)
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Number |
Date |
Country |
Parent |
307139 |
Feb 1989 |
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Parent |
935661 |
Nov 1986 |
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