AMR System Based on GRPS Technology

AMR System Based on GRPS Technology

Automatic Meter Reading (AMR) systems are common around the world today, and they continue undergoing development. To solve the difficulty for data collection and centralization, General Packet Radio Service (GPRS) would be one of several options to apply.

System Architecture of AMR System

Figure 1: AMR System Architecture

GPRS is a packet-based wireless communication service that provides data transmission rates from 56 to 114 kbps. Due to the fast data rate and widespread usage in mobile communication worldwide, GPRS has potential to be developed for use in energy metering systems with access to the private/public network over the wireless system.

The Features of GPRS Communication Technology

  1. Fast Speed and Wide Coverage Area – It shortens the access time from the End-Customer Access Point (Domestic-Unit Meters) to the central data server, and it can serve wider coverage areas to minimize the traffic issue.
  2. Network Extensibility - GPRS can be complemented with Internet Protocol (IP), X.25, GSM EDGE, and UMTS, which are all gaining worldwide popularity.
  3. Technology Backup – This is a continuously developing technology on which most suppliers/service providers are still working on for use in worldwide mobile systems.

Figure 1 shows the three parts in AMR Systems: Digital Meter, Transmission Link and Billing Server

Transmission Solution

Low-Power Wide-Area (LPWA) technology provides a new IoT application for cellular applications that were previously coverage and bandwidth limited, including the AMR system.

Figure 2: Block Diagram for HL6528RD External Interface

Sierra Wireless AirPrime Product Family is fully compliant with the new 3GPP Release 13 Standard of LPWA. Its HL Series is the first released embedded module for deploying on CAT-NB1 networks. CAT-NB1 is an LPWA standard for 2G communication of up to 65 kbps data rates and is ideal for real-time and static sensor applications.

The HL6528RD is a good example of a 2G Transmission module which belongs to the AirPrime HL series from the essential connectivity module family featuring a small, scalable, flexible solution in a compact and easy-to-integrate form factor. It has industrial-grade Quad-band GSM/GPRS capabilities (850/900/1800/1900 MHz), and supports serial ports and general I/O (GPIO) for extension functions. Also, it is easy to equip with external antennas.

As shown in Figure 2, HL6528RD performs four digital I/O interfaces – External LNA(GPS), UART, I2C and PCM, which can cater to different interfaces and peripheral connections.

Figure 3: PC Terminal Emulator Output by AT Command Trigger and with Caller ID

To accelerate the development of HL applications for LPWA, Sierra Wireless offers a Development Kit, the HL Series NO Module KIT, which enables use of its fully accessible interface connectors and the SpyTracer tool for data debugging. It lets the users to deploy the environment as close as possible to their application.

Figure 4: Using Beaglebone Black for Evaluating the M2M Application

By connecting a BeagleBone Black via MQTT protocol to the Dev Board (on the Sierra Wireless AirVantage IoT Platform), it can evaluate different M2M cloud solutions, such as Mihini. The Sierra Wireless AirVantage M2M Cloud has built-in support for the Mihini framework.

Figure 5: Sample for Mihini: AirVantage Agent

The above section explains how to create an application model for an application using the AirVantage Agent. In the sample, the serial number is defined. So you need to define it when creating a system on AirVantage.

Here are the Application Note and Code Samples to enable a BeagleBone Black connection to AirVantage using MQTT.

Using HL6528RD in AMR System

Figure 6: GRPS Communication AMR System Block Diagram

The HL6528RD is used to transmit a signal to the existing cellular network. It uses the nature of IP transmission as a “packet”, where the data is sent from the microcontroller to the GPRS circuit, as well the AT command. The AT command triggers the module to establish a wireless connection with the Customer ID to the billing server database, then provides updated power consumption readings.


LPWA Technology is an increasingly popular approach for implementing the IoT. Using the GPRS which is compliant with CAT-NB1, the LPWA option will have an advantage of long lifetime and flexibility of the product. Moreover, using GPRS technology for an ARM system would allow it to take advantage of the already in-place GMS network and its security packet protocol. Other advantages would include its ability to be used worldwide, ample component sources, and good design extensibility.


  1. Secure Low Cost AMR System Based on GPRS Technology,” Alauddin Al-Omary, Wael El-Medany, and Sufyan Al-Irhayim, International Journal of Computer Theory and Engineering, Vol. 4, No. 1, February 2012
  2. AirPrime HL6528RDx Product Technical Specification”, Rev5.0, Doc4117701, Dec.06.2016, Sierra Wireless
  3. Low-Power Wide-Area (LPWA) Technology”, Sierra Wireless
  4. AirVantage User Guide: Build your IoT Project”, Sierra Wireless

About this author

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Barley Li, Applications Engineer at Digi-Key Electronics in Hong Kong, is responsible for sharing technical solutions and industry technology to assist customers with their design projects. He has over 10 years of global electronics distribution experience and previously prepared product briefs and application notes for a semiconductor manufacturer. Barley holds an Electronic Engineering degree from the City University of Hong Kong. In his free time, he enjoys spending time with his son building toy models and playing ball games.

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