Simulation to estimate RF mesh parameters for the AMI in constrained bandwidth

Abstract

Advanced metering infrastructure (AMI) is an important and integral component of Smart Grid. AMI requires a two way communication network to connect metering and load control endpoints spread over the residential area with the head end system. The most challenging part of AMI is to design this last leg of communication network which reliably and securely fulfills the requirement of the coverage, latency, scalability and compliance to country specific standards and regulations at the right cost. RF mesh technology is a proven way to implement the AMI network and this has been proven in the USA where the RF mesh networks have been functioning satisfactorily for more than a decade in the sub 1 GHz Industrial, Scientific and Medical (ISM) band with an available bandwidth of 26 MHz. In comparison, India has a narrow ISM bandwidth of only 2 MHz, which raises a doubt on achievement of AMI functionality within this constrained bandwidth. To carry out a high level feasibility for India, the relevant AMI data load and throughput requirements were estimated on the basis of data collected from published work and also through a survey involving Indian experts from utilities, regulatory bodies and metering companies. Based on the Pareto analysis of the estimated AMI data, the use case of ‘interval data push’ by the residential meters was considered for network simulation in a real world scenario of RF mesh AMI network. Utilizing only 20 % of the network capacity, for the estimated AMI data throughput of about 20 MB/day, the simulation exercise resulted in an estimate of size of network accommodating about 4800 endpoints per collector based on the acceptable latency of 5 s per hop.