standard T2 as shown in 141. Thus: where r,, is the input reflection coefficient measured with the through standard. The sign of r is positive if the reflection standard is a nominal open circuit and negative for a nominal short circuit. The first two de-embedding parameters, ps and kr, are obtained by using the data of standard T, and its associated matrix M, as follows [4]: where --_ -Mi = m , , -bm,, -dm,, + bdm,, M;, = m , , -am,, -?m12 + Ztm, and m,,, m,,, m,,, m,, are the elements of matrix M,. Eqs. (41, (51, and (7).De-embedding Process. The de-embedding coefficients can be used to de-embed any arbitrary two-port device data, represented by matrix L, by applying the following formulas to obtain the de-embedded parameters V The remaining unknowns, ks and pr, are obtained from ABSTRACT A compact structure for a microwave bandpass filter which uses both microstrip lines and lumped elements is proposed. These filters exhibit broad low-spurious stopbands, a highly suppressed second passhand, and small size. A 4.3-GHz 23% bandwidth 5-section prototype has been tested and shows good performance. These filters could find applications in radar and communication systems. ABSTRACT A low coupling loss of -1.34 dB has been achieved between a laser diode emitting at around 1.55 p m warielength and a high numerical aperture MCVD single-mode fiber by fabricating a conical microlens on the end surjace of the fiber. Also for the same source a coupling loss of about -3 dB has been a c h i e d when a conventional MC1'2) singlemode fiber with a core diameter of 7.3 p m was used.
