摘要:

The possibility of using larger delay time values in CPFSK systems with tight IF filtering to improve the bit error rate performance is investigated. The analysis uses a previously developed rigorous model for CPFSK systems with tight IF filtering. It is shown theoretically that a resulting system sensitivity of 36.2 photoelectrons per bit time for a 10−9bit error rate can be obtained for a modulation index of 0.8 and that the optimum system can be operated with a laser linewidth that is 0.87 times the linewidth tolerated by a DPSK system with tight IF filtering.

DOI:10.1049/ip-j.1992.0028

出版商:IEE    

年代:1992

数据来源: IET

摘要:

There are several reports on the measurement of the refractive indices of single-crystal rutile. Whereas the ordinary refractive indices estimated are in close agreement over a wide range of wavelengths, there is a significant difference in the corresponding values of the extraordinary refractive indices. Observations on the ‘prism-coupling technique’ using rutile prisms are reported to show that, for the refractive indices of rutile, the work of W.H. Bond represents a better standard.

DOI:10.1049/ip-j.1992.0029

出版商:IEE    

年代:1992

数据来源: IET

摘要:

A simple approach based on the scalar finite element method is described for the evaluation of the effective index, modal field profile, and far-field pattern of the guided mode of an optical rib waveguide and of the coupling efficiency of a butt-joint structure of two single-moded rib waveguides. Calculations are performed for several different rib waveguide structures, and the accuracy of the present approach is examined and assessed by comparing the results obtained with the other existing methods.

DOI:10.1049/ip-j.1992.0030

出版商:IEE    

年代:1992

数据来源: IET