Energy Harvesting FAQ’s

To connect a wireless transmitter and a receiver, they have to be coupled. This is called pairing. The receiver is switched to pairing-mode by pressing a push button. If a signal is triggered with one or more wireless transmitters, all the transmitters will pair with the one receiver.

Transmitting and receiving reliability of wireless signals depends on various factors. In addition to technical values, e.g. transmission power of the wireless transmitter and sensitivity of radio receivers, environmental conditions are essential.

Barriers – like walls and ceilings in buildings – dampen and reflect radio waves affecting the transmission reliability. Interference of radio transmission can be caused by other radio participants when they are using the same frequency bands. Instructions for operation and installation of our wireless technology can be found in the application notes.

Barriers – like walls and ceilings in buildings – dampen and reflect radio waves. Therefore it is important to ensure that as few walls and ceilings are between the wireless transmitters and receivers, as possible. To minimize the disturbance caused by other radio participants, the radio telegrams should be transmitted several times. Instructions for operation and installation of our wireless technology can be found in the application notes.

Basically two factors are important for selecting a frequency: the technical propagation characteristics and regularity and legal aspects. Regarding the technical propagation characteristics, it is generally correct that lower frequencies have a greater transmission range. In addition, the propagation characteristics in buildings get better with lower frequencies. These so-called Sub-GHz-Frequencies, which means below 1 GHz, become therefore very attractive.

Due to national and international regulations not all frequencies can be used everywhere. Only the 2.4 GHz band is based on the definition of the ITU (International Telecommunication Union), a so-called ISM Band. It is applicable all over the world. The 868MHz frequency band is just applicable in Europe and China. In USA and Canada this band cannot be used. In this case it is necessary to use the 915 MHz band.

The task of the antenna is to radiate the produced transmission power with minimal losses into the surrounding environment (transmitting antenna) or to capture maximum transmission power (receiving antenna). As a consequence, the orientation of the antenna can have a critical effect on the radio characteristics. ZF wireless products use a wire antenna or a PCB antenna. In the case of a wire antenna, the insulated wire leads out of the switch housing. To ensure an optimal radiation it is important that the antenna is not twisted. Direct contact or indirect shielding through metal surfaces should also be avoided. This also applies for products with an integrated antenna that is directly implemented into the conducting path on the electronic board. For these products you will find information with regard to the installation in the respective application notes.

The so-called resonance frequency is a very important factor of the antenna construction. At this  resonance frequency the losses from the antenna are minimal. The resonance frequency is usually the requested communication frequency and confirmed in the settings by the radio chip. The antenna was precisely designed for this frequency which means the length of the wire antenna corresponds exactly to the constructive design. Therefore, reducing the length of the antenna will lead to transmission losses and should be avoided.

The radio