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US4013981A Expired / Lapsed US ⏱️ 0.0 years remaining

Constant-resistance coupled-line type equalizer

Assignee: KDDI Corp
•
Filing: 1975-06-19
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Granted: 1977-03-22
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Expires: 1995-06-19
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Abstract

Abstract An equalizer having improved amplitude characteristics and phase characteristics of more than several hundred MHz has been found by using a four port directional coupler. The equalizer consists of coupled lines, and two far end ports of the directional coupler are grounded through two resistances R 1 , respectively; while interconnecting the two far end ports through a resistance r, an input port is formed at one of the near end ports of the directional coupler, and an output port is formed at the other end thereof, said resistances substantially satisfying the relation of G.sub.1 (G.sub.1 +2g)=G.sub.0.sup.2 Z.sub.0o Z.sub.0e =R.sub.0.sup.2 where, G 1 =1/R 1 ,g=1/r,G 0 =1/R 0 , R 0 being resistance of a power source and a load, Z Oo being the odd mode impedance of a coupled line, and Z 0e being the even mode impedance of the same.

Inventors

  • 👤 Sotokichi Shintani
  • 👤 Michitoshi Tamori
  • 👤 Nobuo Nagai

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 01:25
CPC Classifications
H; H04; H04B; H04B3/00; H04B3/02; H04B3/04; H04B3/14; H04B3/143; H04B3/145

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 99 words
An equalizer including a four port directional coupler using strip coupling lines, characterized in that two far end ports of the directional coupler are grounded through two resistances R 1 , respectively, while interconnecting the two far end ports through a resistance r, an input port is formed at one of the near end ports of the directional coupler, and an output port is formed at the other end thereof, wherein G.sub.1 (G.sub.1 +2g)=G.sub.0.sup.2 where, G 1 =1/R 1 , g=1/r, G 0 =1/R 0 , and R 0 is the resistance of a power source and a load.
Claim 2
Dependent Claim 99 words
An equalizer including a four port directional coupler using strip coupling lines, characterized in that two far end ports of the directional coupler are grounded through two resistances R 1 , respectively, while interconnecting the two far end ports through a resistance r, an input port is formed at one of the near end ports of the directional coupler, and an output port is formed at the other end thereof, wherein G.sub.1 (G.sub.1 +2g)=G.sub.0.sup.2 where, G 1 =1/R 1 , g=1/r, G 0 =1/R 0 , and R 0 is the resistance of a power source and a load.
Claim 3
Dependent Claim 56 words
An equalizer according to claim 1, wherein a plurality of said four port directional couplers are concatenated, the far end directional coupler of said plurality of directional couplers has said resistances R 1 and r connected thereto, and overall input resistance of the coupled-line type network thus formed is constant, whereby, said equalizer is made variable.
Claim 4
Dependent Claim 15 words
An equalizer according to claim 1, wherein a plurality of said directional couplers are concatenated.
Claim 5
Dependent Claim 223 words
An equalizer comprising a first four port directional coupler having a pair of strip lines A, C and B, D, and having the near ends A, B and the far ends C, D; a second four port directional coupler having a pair of strip lines E, G and F, H, and having the near ends E, F and the far ends G, H; a first impedance (1/G 1 ) connected between the terminal D and the ground; a second impedance (1/G 1 ) connected between the terminal E and the ground; means for connecting the terminals C and G; means for connecting the terminals B and F; a third impedance (1/g) connected between the terminals D and E; an input terminal connected to the port A; and the output terminal connected to the port H; wherein the following conditions are satisfied. Z.sub.0e.sup.(A) .sup.. Z.sub.0o.sup.(A) = R.sub.0.sup.2 z.sub.0e.sup.(B) .sup.. Z.sub.0o.sup.(B) = R.sub.0.sup.2 g.sub.1 (g.sub.1 +2g)=G.sub.0.sup.2 g.sub.0 =1/r.sub.0, g.sub.1 =1/r.sub.1, g=1/r where Z 0e .sup.(A) is the even mode impedance of the first strip line, Z 0o .sup.(A) is the odd mode impedance of the first strip line, Z 0e .sup.(B) is the even mode impedance of the second strip line, Z 0o .sup.(B) is the odd mode impedance of the second strip line, R O is resistance of a power source and a load,
Claim 6
Dependent Claim 223 words
An equalizer comprising a first four port directional coupler having a pair of strip lines A, C and B, D, and having the near ends A, B and the far ends C, D; a second four port directional coupler having a pair of strip lines E, G and F, H, and having the near ends E, F and the far ends G, H; a first impedance (1/G 1 ) connected between the terminal D and the ground; a second impedance (1/G 1 ) connected between the terminal E and the ground; means for connecting the terminals C and G; means for connecting the terminals B and F; a third impedance (1/g) connected between the terminals D and E; an input terminal connected to the port A; and the output terminal connected to the port H; wherein the following conditions are satisfied. Z.sub.0e.sup.(A) .sup.. Z.sub.0o.sup.(A) = R.sub.0.sup.2 z.sub.0e.sup.(B) .sup.. Z.sub.0o.sup.(B) = R.sub.0.sup.2 g.sub.1 (g.sub.1 +2g)=G.sub.0.sup.2 g.sub.0 =1/r.sub.0, g.sub.1 =1/r.sub.1, g=1/r where Z 0e .sup.(A) is the even mode impedance of the first strip line, Z 0o .sup.(A) is the odd mode impedance of the first strip line, Z 0e .sup.(B) is the even mode impedance of the second strip line, Z 0o .sup.(B) is the odd mode impedance of the second strip line, R O is resistance of a power source and a load,
Claim 7
Dependent Claim 21 words
An equalizer according to claim 4, wherein said first and second strip lines are curved in a symmetrical half circle form.

References Cited (Backward Citations)

US3372350A Cited
US3382465A Cited
US3600707A Cited
US3899756A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-03-21 1980-09-20 1981-03-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-03-21 1984-09-20 1985-03-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-03-21 1988-09-20 1989-03-22 $7700.00 Window Closed / Lapsed

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