3.2 Frequency characteristics of an SMR device
Figure 7 shows the frequency response of an SMR device, in which, a large returning loss of 30 dB at 1.09 GHz can be observed. The discrepancy between designed and practical resonance frequencies can be attributed to the inaccuracy in the thickness of piezoelectric layer. The transistor of PHILIPs BFR 505 is adopted to construct the high frequency amplifier.