In this article, we have proposed an accurate calibration method for measuring photodetector wideband response with optical heterodyne measurement technique. The experimental result ranging from 0 to 48.65 GHz indicates that the proposed calibration method can effectively remove the errors introduced by extra fixture as well as laser output fluctuations. Good agreement between the calibrated frequency response and the data provided by the manufacturer has been achieved. The proposed method can improve the accuracy for optical heterodyne measurement technique and reduce the requirements in both laser output stabilities and fixture frequency performance, which is suitable to characterize the photodetector frequency response in an ultrawide frequency range. REFERENCES

Design of a tunable fully differential GHz range Gm-C lowpass filter in 0.18 m CMOS for DS-CDMA UWB transceivers, IEEE Int Symp Circuits Systems (2006), 21-24. 6. L.T. Bruton, Multiple RC-active filter design with emphasis on GIC realizations, IEEE Trans Circuits Systems CAS-25 (1978). ABSTRACT: By properly loading branch strips to a monopole antenna fed by a coplanar waveguide (CPW) feedline, an antenna with good impedance matching in a wide triple-band covering PCS-1900/UMTS-2100 and the 5.2/5.8 GHz WLAN systems is designed. Prototype of the proposed antenna has been constructed and experimentally studied. The measured results not only explore wide Ϫ10 dB impedance bandwidths of 21, 18, and 15% at the operating bands of 2.16, 5.27, and 7.52 GHz, respectively, but also show good agreement with the numerical predictions.

No abstract

No abstract