The Controlant Monitoring System is an automatic wireless monitoring system, which is used in various applications where automatic measurements of environmental variables (e.g. temperature, humidity) are required.
The basis of the system is a star-shaped wireless network where multiple wireless loggers can transmit measurements to a gateway unit which sends the data to a central database server via the mobile network. The data can then be accessed from an internet connected computer from a web browser interface.
Controlant wireless loggers run on a battery. The gateways have a rechargeable internal backup battery which can keep the system running for 12-24 hours (depending on usage) in case of power failure. The battery is a rechargeable lithium-ion battery.
System Overview
Figure 2: Overview of the Controlant wireless monitoring system
Multiple loggers can be located on each location, connecting to one or more gateways. Data from multiple locations is gathered in a database, where customers can access it in a single interface.
Theory of Operation
Figure 3: Block diagram of the Controlant wireless system
A functional block diagram for the CO 13.01 wireless logger is shown in Figure 3. The RF module CC1101 is a low-power sub-1 GHz RF transceiver operating in the 868 MHz to 915 MHz ISM band.
The system has two operating modes. The first operating mode is at a symbol rate of 4.75 kbps, and a bit rate of 38 kbps. GFSK modulation is used with 20 kHz deviation. This operation mode is used for all communications in the 868MHz band as well as for FHSS mode in the 915 MHz band. The second operating is at a symbol rate of 475 bps, and a bit rate of 4 kbps. 2-FSK modulation is used with 550 kHz bandwidth. This operation mode is used for all synch package communication in the 915 MHz band.
A 3.6 VDC battery is supplied to the RF module. The module transmits with a maximum power of 11 dBm into an external antenna. This module does not transmit for more than 54 ms over any 1 s time period and fulfills all duty cycle limits on the 868MHz band and uses 121 channels for FHSS in the 915 MHz band with 200 kHz channel spacing and 75 kHz channel bandwidth (20 dB).
Logger Operation
The purpose of the Controlant wireless logger is to measure environment variables such as temperature and humidity. The loggers automatically transmit measurements to a nearby gateway, which forwards the data to a central database. The wireless sensor communicates with the gateway on the license free ISM bands (868 MHz for EU and 915 MHz for North America).
System Components
The system consists of following devices, software and systems:
Loggers
- For EU market
For US market
CO 13.02 - Temperature & Humidity Logger - Not available
CO 17.01 – Multipurpose Logger - Not available
Gateway
- For EU market
- CO 01.01 - Gateway
- CO 01.02 – Vehicle Gateway - Not available
- For US market
- CO 11.01 - Gateway
- CO 11.02 – Vehicle Gateway Not available
- For EU market
Mobile Network (3G)
Controlant Gateways relies on 3G cellular networks to transmit loggers data to the Controlant cloud. Same rules applies to these radio communications as all other mobile and high frequency communications. If the signal is low or bad, the functionality of the system will be effected. However, the system takes that into account, store the data in the loggers itself and sends the data to the Controlant cloud when the cellular connection has been re-established.
Wall types in a warehouse can effect the signal quality as well as the device installation itself. Further information regarding wireless installation and wall types can be found in 1.3.1 General Wireless Setup
Database
User Interface