Differential signal transmission cable

A differential signal transmission cable, comprising:

• a pair of differential signal lines arranged in parallel to each other;
• an insulation for bundle-covering the pair of differential signal lines;
• and
• a shield conductor wound around an outer periphery of the insulation,
• wherein the insulation is configured such that an outer circumference thereof in a cross section perpendicular to a longitudinal direction thereof has an oval shape formed with a continuous convex arc-curve,
• wherein the outer circumference of the insulation comprises a first curved portion with a pair of symmetrical elliptical arcs located at both ends in a first direction along the arrangement direction of the pair of differential signal lines and a second curved portion with a pair of symmetrical elliptical arcs located at both ends in a second direction orthogonal to the first directional, and
• wherein the cable satisfies a condition represented by the following formula (1) where a minor or major axis of the elliptical arc of the first curved portion in the first direction is 2a1, a major or minor axis of the elliptical arc of the first curved portion in the second direction is 2b1, a major axis of the elliptical arc of the second curved portion in the first direction is 2b2, a minor axis of the elliptical arc of the second curved portion in the second direction is 2b2, a phase angle of a connecting point between the elliptical arc of the first curved portion and the second curved portion is θ0 and a phase angle of a connecting point between the elliptical arc of the second curved portion and the first curved portion is φ0,
• tan
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• ϕ
• 0
• =
• a
• 1
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• b
• 2
• a
• 2
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• b
• 1
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• tan
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• θ
• 0
• .
• formula
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• (
• 1
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