Coupling Matrix Synthesis of Nonreciprocal Lossless Two-Port Networks   using Gyrators and Inverters
  A coupling matrix technique is presented for the synthesis of nonreciprocal lossless two-port networks. This technique introduces complex inverters to build the nonreciprocal transversal network corresponding to the nonreciprocal coupling matrix. It subsequently transforms this matrix into canonical topologies through complex similarity transformations. The complex inverters in the final topology are transformed into real inverters and gyrators for implementation simplicity. A second-order example is then given to illustrate the proposed technique. Possible implementations of the gyrators involved in the final design are also discussed. 
Qingfeng Zhang, Toshiro Kodera, Shuai Ding, and Christophe Caloz
physics.optics