Magnetostatic Volume Wave Delay Lines with Stepped Ground Planes

A magnetostatic forward volume wave delay line was divided into sections each with a different ground plane spacing. The length of each section was optimized so that the total group delay, i.e., the summation of the delay in each section, showed a minimum phase error from a quadratic phase with frequency characteristic. Using this technique a delay line with 600 MHz bandwidth, 50 nS differential delay and phase error < +- 16° has been demonstrated at X-band.