Affiliation:
1. School of Information Science and Technology Southwest Jiaotong University Chengdu China
2. Information Materials and Intelligent Sensing Laboratory of Anhui Province Anhui University Hefei China
3. China Telecommunication Technology Labs China Academy of Information and Communications Technology Beijing China
Abstract
AbstractPassive intermodulation (PIM) is usually expressed by the third‐order intermodulation power excited by two‐tone signal, which has limitations in characterising nonlinear distortion of signal in actual communication system. The effect of PIM on modulated signals are analysed at both the transmit and receive port with multiple passive nonlinear sources. Four types of coaxial connectors are adopted to represent four different levels of PIM. The equivalent circuits of PIM sources in series or parallel are proposed. With the circuit simulations and theoretical modelling, the effect of PIM on the analog and the digital modulation signals are analysed respectively. Two indexes of adjacent channel leakage ratio and error vector magnitude are modelled, showing the PIM effect at transmit port. A system model of a transmit‐receiver is provided, investigating the effect of PIM on the symbol error rate in a receiver. The effects of PIM distortion on different modulated signals are observed both in experimental measurements and simulation tests, verifying the theoretical models.
Publisher
Institution of Engineering and Technology (IET)
Subject
Electrical and Electronic Engineering