Patent ID: 8629715
Filing Date: 2014-01-14
Classification: G06F,H04B

Abstract:
1. A circuit configured to propagate local oscillator signals from a local oscillator to a communication unit, the circuit comprising: a first pair of lines connected to receive differential in-phase signals generated by the local oscillator and output those signals to the communication unit; and a second pair of lines connected to receive differential quadrature signals generated by the local oscillator and output those signals to the communication unit; said lines being arranged such that at least once along a length of the first pair of lines, one of the first pair of lines crosses the other one of the first pair of lines to create a first twist, at least once along a length of the second pair of lines, one of the second pair of lines crosses the other one of the second pair of lines to create a second twist, and the first twist is offset from the second twist along the length of the first pair of lines such that: a first line of the first pair is, in use, magnetically coupled to a first line of the second pair for a first portion of its length with a coupling coefficient K, and magnetically coupled to a second line of the second pair for a second portion of its length with a coupling coefficient −K; and a second line of the first pair is magnetically coupled to the second line of the second pair for a third portion of its length with coupling coefficient K, and magnetically coupled to the first line of the second pair for a fourth portion of its length with coupling coefficient −K; the sum of the first and third portions being substantially equal to the sum of the second and fourth portions.