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Aeroqual AQM60 User Guide
Solution 3: DDNS
Using dynamic IP addresses is often necessary since many ISPs do not provide static IP addresses. The
Dynamic Domain Name System (DDNS) is used to conver
t a device’s name into a dynamic IP address so
that remote devices can communicate with the control centre using a fixed domain name. DDNS takes care
of the Dynamic IP address of a device, and DNS the static IP address of a device.
With most remote GPRS devices, you need to apply for a hostname for each of the devices handled by the
DDNS server. When GPRS devices get an IP from the carrier, they will automatically connect to the GPRS
network. Each time a GPRS device’s built-in DDNS client gets a new IP address, it will send the IP address
to the DDNS sever.
Aeroqual has used www.dyndns.com successfully to communicate with AQM60 instruments.
For further details visit the Moxa company website
3.4. Other Communication Options
3.4.1. RF Modem
The XStream 2.4 GHz RS-232/RS-485 radio modem provides long range, low power wireless serial
communication with the AQM unit. Two modems are typically required to connect between the AQM and a
computer. Units are DIP Switchable for RS-232, RS-422, and RS-485 support. Specifications are given
below:
For more details see www.maxstream.net
3.4.2. GSM Modem
Aeroqual typically integrates the Fargo Maestro 100 Dual band GSM MODEM for remote data access. This
provides a serial link to the AQM from a computer via the GSM network. Two modems are typically needed
to establish a GSM link between computer and AQM. Please read the Fargo Maestro 100 manual for
detailed instructions on configuration and use.
Interface connections:
SIM holder
15 pin Sub-D connector (serial and audio connection)
SMA antenna connector (50 ohm)
Safety Precautions:
The modem generates radio frequency (RF) power. When using the modem care must be taken on
safety issues related to RF interference as well as regulations on RF equipment.
Outdoor RF line of sight range 5 km
Transmit power output
50mW (17 dBm)
Receiver sensitivity
-105 dBm (@9,600 bps),-102 dBm
(@19,200 bps)
Spread spectrum
FHSS (Frequency Hopping Spread
Spectrum)
RF data rate
10,000 bps (@9,600 bps) or 20,000
bps (@19,200 bps)
Frequency range
2.4000 - 2.4835 GHz