FAQ
What is the maximum working distance ?
The maximum working distance for power transmission depends on the power level emitted, the Tx and Rx antennas being used and the electrical consumption of the sensor. By using the AST-02 family sensor tags the typical working distance is up to 100 meters.
How much power is available at the sensor level ?
Available power at the sensor side is typically in the low milliwatt and microwatt range. It depends on transmission distance, antenna performance, embedded capacitor size and sensor operating voltage.
Which types of sensors can be connected ?
A tag model offers two analog interfaces with a voltage range of 0 to 5 Volts, one digital SPI interface and 1 digital I2C interface. There are also tag models with integrated sensors (temperature, pressure, humidity, acceleration, inclination, light and magnetic field) or those designed for specific sensors (potentiometer, strain gauges, incremental encoder, proximity sensor…).
Which frequencies are supported ?
The power transmitter PWT-04 emits a continuous wave in the ISM band, at a frequency of 2.45 GHz. The power harvesting tags are designed for a frequency range of 2.4 to 2.5 GHz. The bidirectional communications module operates at a frequency of 868MHz.
Can I harvest energy from Wi-Fi ?
Ambient energy from Wi-Fi routers etc. is typically not strong enough to power GreenWake Technologies tags at a useful distance. The use of a dedicated power source, such as the PWT-04 transmitter, is required.
Can I use other energy sources ?
GreenWake Technologies tags can be powered by any RF (microwave) source, emitting sufficient power in the 2.4 to 2.5 GHz spectrum. GreenWake Technologies, however, recommends AST tags to be used with the PWT-04 transmitters, to ensure reliable performance.
Which antennas can be used ?
PWT-04 transmitters and AST tags are designed to work with standard 50 Ohm antennas. Antennas need to be matched to the frequency range being used.
Can the products be configured ?
The PWT-04 transmitter’s embedded software can be used to adjust the output power across the range of 1 to 4W. The AST tags can be configured remotely, including sensor output voltages, continuous or pulsed mode. AST tags can also be configured, by GreenWake Technologies, to your specific needs for multiple digital sensors using SPI and I2C protocols.
Can I use GreenWake Technologies technology in any country ?
GreenWake Technologies products are currently certified for Europe.
Is there interference with other devices ?
Any device generating radiofrequency signals can interfere with other such devices. The interference potential depends on field strength, frequency band and the ability of the receiver to discriminate noise. GreenWake Technologies has performed empirical testing with mobile phones and Wi-Fi devices using Direct Sequence Spread Spectrum (DSSS) and found no degradation in device performance at practical distances. Interference within the Wi-Fi band is further reduced by automatic channel picking of Wi-Fi devices and the use of directional antennas.
Is the technology proprietary ?
Our technology is protected by international patents. Please contact us for any licensing needs.
Is the technology safe ?
Our technology uses radio frequency transmissions, already used by household appliances such as mobile phones, alarms, Wi-Fi routers etc. Exposure levels to radiation from a GreenWake Technologies transmitter are significantly lower than from a handheld cell phone. All GreenWake Technologies products are CE marked by an independent certification laboratory and approved for use in Europe.
Which regulatory standards do apply ?
All GreenWake Technologies products are CE marked and compatible with following European standards: EN 60950-1, EN 61000-6-2, EN 55011, EN 301489-1 & -3, EN 300220-1 & -2.