Development of a System for Token Validation in a Prepayment Energy Meter from Wireless Recharge Source without a Server

Abstract

This paper presents a method of Token Validation of a wireless recharge token in Prepayment Energy meter without recourse to any server. Most proposal on wireless recharging have suggested token validation at the server in the Supply Authority’s office. The need for Prepayment Energy Meter to be able to validate token from a wireless source without the help of an intermediary system is highly desirable. The Prepayment Meter is realized with an ADE7755, Atmega328 and Atmega2560 in its circuitry among other components. The ADE7755 gives the load pulses that are measured and recorded by Atmega328P. Atmega2560 manages the units according to consumption. It also controls and monitors the activities of the meter and receives token for recharge from a GSM Short Message Service (SMS) platform using SIM900 as the gateway. It also comprise of a Liquid Crystal Display (LCD) for displaying unit balance and other information. The microcontrollers are programmed in C++ language with a Data Encryption Standard (DES) built in a Labview environment used in the token validation algorithm incorporated in Atmega2560. The results obtained show a mean signaling time for SMS recharging of 20.50s and 100% success rate in wireless recharging showing correct validation of recharge token by the meter. With the results obtained, token recharge from wireless sources, especially the SMS can be validated without recourse to a server anywhere.