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 reatly with the growth of the total number of the carriers. The results are useful for the component designers and the cellular network planners.