Superposition Effect of Passive Intermodulation for Cable Assemblies with Discrete Point-Sources

In order to expand the cell coverage of wireless cellular systems, the number of passive components in wireless systems has been substantially increased. There can be many passive intermodulation(PIM) pointsources even in a device or a radio link, which may add up constructively or destructively. A modified point-source model with lossy components is proposed to evaluate the superposition effect of the forward and refl ected PIM in case of series connection. The index of the series connection factor(SCF) is employed for systems that incorporate multiple PIM sources to predict the important characteristics of the cumulative PIM, such as the maximum and minimum values and the limit form. Furthermore, some initial experimental results are given out and the deviation in the above-mentioned prediction is also analyzed.

Performance of a two-state quantum engine improved by the superposition effect

The performance of a two-state quantum engine under different conditions is analyzed. It is shown that the efficiency of the quantum engine can be enhanced by superposing the eigenstates at the beginning of the cycle. By employing the finite-time movement of the potential wall, the power output of the quantum engine as well as the efficiency at the maximum power out- put （EMP） can be obtained. A generalized potential is adopted to describe a class of two-level quantum engines in a unified way. The results obtained show clearly that the performances of these engines depend on the external potential, the geometric configuration of the quantum engines, and the superposition effect. Moreow^r, it is found that the superposition effect will en- large the optimally operating region of quantum engines.

Superposition effect of passive inter-modulation for systems operating in multiple carriers

Nowadays, more carriers and components are used in cellular networks to satisfy the requirement of high-speed data service. The increase of carriers and components may result in serious problem of passive inter-modulation （PIM）. This paper investigates the superposition effect of 3rd-order and 5th-order PIM under multicarrier scenarios with the channelized scheme （CS） and the multiplexed scheme （MS）. We use the concept of ＇effective hit＇ and the cumulative inter-modulation factors （CIFs） to evaluate the cumulative PIM product strength on each individual carrier within the receive signal band. Furthermore, with the simulator based on Monte-Carlo method, the group inter-modulation factor （GIF） is calculated to measure the average superposition effect for multiple carriers compared with the benchmark case. The simulation results show that, compared with the CS, the strength of PIM product with the MS does not increases so greatly with the growth of the total number of the carriers. The results are useful for the component designers and the cellular network planners.