Factors Influencing Radio Waves & Range in Lighting Applications, Study notes of Technology

Download Factors Influencing Radio Waves & Range in Lighting Applications and more Study notes Technology in PDF only on Docsity! Lighting Controls Radio technology in lighting applications At a glance At a Glance - Radio technology in lighting applications | 05-2022 | 1.2 | en Table of contents c 1 / 30 ... 1. About this document  2 2. Basics of electromagnetic waves  3 3. Radio waves and their propagation  5 4. Coexistence of different radio systems  6 5. Factors influencing radio waves  7 5.1. Reflection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 5.2. Interference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 5.3. Diffraction and shadowing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 5.4. Damping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 6. Range of radio waves  15 7. Installation of the radio components in the luminaire  17 8. Influence of metal parts on the antenna  18 9. Metal dampening and shadowing  20 10. Structural measures for radio-compatible metal luminaires  23 11. Measurement of the signal quality  24 12. Signal range test with basicDIM wireless  24 13. Influence of the spatial conditions on the luminaire  27 13.1. Ceiling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 13.2. Materials in the walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 13.3. Windows and panes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 13.4. Other radio systems available on site . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 13.5. Floor plan of the building . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 13.6. "Island problem" . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 14. Explanations of used terms and abbreviations  30 At a Glance - Radio technology in lighting applications | 05-2022 | 1.2 | en Basics of electromagnetic waves c 4 / 30 ... At a Glance - Radio technology in lighting applications | 05-2022 | 1.2 | en Radio waves and their propagation c 5 / 30 Radio waves are electromagnetic waves that move in the low frequency range. They are used to transfer information. In free space, radio waves propagate spherically. The signal strength decreases quadratically with distance. From a certain distance on, the signal is so weak that it can no longer be received without errors or is masked by the surrounding noise. The following graphic shows how the signal strength decreases with distance. ... At a Glance - Radio technology in lighting applications | 05-2022 | 1.2 | en Coexistence of different radio systems c 6 / 30 Different frequency bands are subject to regional restrictions. The only frequency band that is freely available worldwide is the 2.4 GHz frequency band. It is used for a variety of different applications such as: By using the same frequency band all these applications can influence each other. Various methods have been developed to make sure that these technologies can be used in parallel and without interference. The right channel selection in WLAN, for example, can guarantee a problem-free parallel operation. ... WLAN_ Bluetooth_ Thread_ ZigBee_ etc._ ½ CAUTION! WLAN, Bluetooth, Thread etc. all use the same frequency band and can influence and interfere with one another._ Depending on the load, a WLAN can interfere with other applications more or less._ An analysis of the occupancy in the frequency band before installation over a longer period of time is necessary in order to make the right channel selection (occupancy is dynamic and can change at any time!). _ At a Glance - Radio technology in lighting applications | 05-2022 | 1.2 | en Factors influencing radio waves c 9 / 30 Cancellation of the signal 5.3. Diffraction and shadowing When radio waves hit an obstacle, the radio waves are diffracted. How and how strongly the radio waves are diffracted, depends on the following factors: Diffraction has both positive and negative effects on the propagation of radio waves: The following graphics illustrate diffraction and shadowing for different obstacles: The frequency of the radio wave: The higher the frequency, the lower the diffraction angle and vice versa._ The size of the obstacle or the passage between obstacles: See graphics below._ Positive: Because of diffraction, radio waves can reach areas that don't have a line of sight between sender and receiver (because of the obstacle). _ Negative: There are areas behind the obstacle in which shadowing occurs. Shadowing refers to areas in which radio waves cannot propagate due to the spatial conditions. In such areas there is no or only poor reception. The type and size of the shadowing depends on the diffraction of the radio waves. _ At a Glance - Radio technology in lighting applications | 05-2022 | 1.2 | en Factors influencing radio waves c 10 / 30 Diffraction and shadowing behind obstacles with a narrow passage Diffraction and shadowing behind obstacles with a wider passage At a Glance - Radio technology in lighting applications | 05-2022 | 1.2 | en Factors influencing radio waves c 11 / 30 Diffraction and shadowing behind surface area obstacles ... In addition to the spatial conditions on site, the construction of the luminaire itself can lead to shadowing and deteriorate the propagation of radio waves: If the radio connection between individual luminaires in the room is poor, the following measures can be useful: ½ CAUTION! Change of position of the luminaire_ Adding more luminaires_ Adding a basicDIM wireless module, which only functions as a bridge_ At a Glance - Radio technology in lighting applications | 05-2022 | 1.2 | en Factors influencing radio waves c 14 / 30 ... Sometimes the weakening effect of metals is not obvious. Tinted windows, for example, are often vaporized with metal and also lead to this effect. I NOTICE At a Glance - Radio technology in lighting applications | 05-2022 | 1.2 | en Range of radio waves c 15 / 30 The range of radio waves depends on many factors and is difficult to predict! The influencing factors include: Larger ranges can only be reached with a combination of optimal luminaire design and appropriate installation. The following graphic illustrates the relationship between transmission level and range and how a less than optimal luminaire design has a direct effect on the range! Antenna_ Transmission power of the radio module_ Luminaire design_ Spatial conditions_ This following graphic and the distance information it contains do NOT apply to the 2.4 GHz frequency band, but to radio waves with: ½ CAUTION! 1 MHz_ 100 mW transmission power_ At a Glance - Radio technology in lighting applications | 05-2022 | 1.2 | en Range of radio waves c 16 / 30 The black line shows the received transmission level over increasing distances (logarithmic). In this representation, the level decreases linearly over distance. With a receiver sensitivity of -100 dB, this results in a range of 10 km. This represents the optimum (radio module in the free field without disturbing influences). In comparison, the other two lines show the transmission level with an additional attenuation of 10 dB and 20 dB. At 10 dB attenuation the range is reduced from 10 km to 3.15 km, at 20 dB attenuation the range is reduced to 1 km. ... By attenuating the transmission level, the range of the radio signal is significantly reduced: ½ CAUTION! -10 dB in level means only a third of the maximum range._ -20 dB in level means only a tenth of the maximum range._ At a Glance - Radio technology in lighting applications | 05-2022 | 1.2 | en Influence of metal parts on the antenna c 19 / 30 ... At a Glance - Radio technology in lighting applications | 05-2022 | 1.2 | en Metal dampening and shadowing c 20 / 30 Radio modules must be installed in luminaires in such a way that the attenuation and shadowing of the radio waves in the room is as low as possible. The attenuation and shadowing is different depending on the construction, design and mounting of the luminaire. The following graphic shows how a radio module should be installed ideally: The antenna can transmit through the plastic diffuser into the room without hindrance, the propagation of radio waves into the ceiling is weakened by the metal base of the luminaire. If the radio module is installed between metal parts and the ceiling, the radiation of the antenna into the room is hindered by the metal. Such a structure would be very unfavorable in terms of radio transmission. In the laboratory, such a structure can still deliver good measurement results since the luminaire is open at the top. In the real environment, however, the luminaire could be installed on a reinforced concrete or metal ceiling and become a Faraday cage, which hardly allows radio waves to penetrate to the outside. Laboratory conditions: At a Glance - Radio technology in lighting applications | 05-2022 | 1.2 | en Metal dampening and shadowing c 21 / 30 Installation situation: Komponenten in der Leuchte, insbesondere solche aus Metal, können Funksignale erheblich beeinflussen. Dies kann dazu führen, dass die Signalstärke je nach Richtung variiert. Das folgende Beispielbild verdeutlicht dies. Das Funksignal wird nach unten durch eine dort angebrachte Metallplatte und seitlich durch einen dort befindlichen Treiber gedämpft. Die Signalstärke ist in diesen Richtungen schwächer. Depending on the orientation of the luminaire, this results in signal strengths and ranges that vary in quality: At a Glance - Radio technology in lighting applications | 05-2022 | 1.2 | en Measurement of the signal quality c 24 / 30 In order to obtain a reliable statement about the signal quality of the respective luminaire, it is advisable to measure the luminaire professionally. The signal quality can be estimated by performing two measurements via the app (one with the radio module inside the luminaire and one with the radio module outside the luminaire) and then comparing the results. The normal signal strength of an open radio module is around -40 dBm. The lower limit is around -90 dBm. Communication is no longer possible with an even lower value. Signal quality Level in dBm Well > -50 dBm Medium -65 dBm to- -50 dBm Bad < -65 dBM Testing the signal range is essential to obtain information about the quality of the luminaire. Tests should be done: By attenuating the transmission level (in this case by the luminaire itself) there is a significant reduction in the range of the radio signal: The final installation situation must also be taken into account! Reinforced concrete and metal ceilings can cause significant problems! ½ CAUTION! -3 dB corresponds to halving the signal strength._ -10 dB corresponds to a tenth of the original signal strength._ This chapter describes how to carry out a signal range test with the basicDIM Wireless from Tridonic. The description is specific for this device and cannot be transferred to other devices of a similar type. I NOTICE From luminaire to luminaire_ From mobile device to luminaire_ At a Glance - Radio technology in lighting applications | 05-2022 | 1.2 | en Signal range test with basicDIM wireless c 25 / 30 ... From different angles, directions and distances_ At every stage of the luminaire development_ For the test it is important that the basicDIM wireless modules and drivers are in the same exact position as in the later installation and are not installed at a different point in the luminaire! Changes in position change the test result and make a new test necessary (signal strength and range)! ½ CAUTION! At a Glance - Radio technology in lighting applications | 05-2022 | 1.2 | en Signal range test with basicDIM wireless c 26 / 30 Two sample luminaires A and B with integrated basicDIM wireless are required for this test . Proceed as follows: 1 Set up a basicDIM wireless test network with these two sample luminaires. 2 Disconnect both sample luminaires from mains. 3 Switch on sample luminaire A again and wait until the basicDIM wireless app connects to it. 4 Switch on sample luminaire B again. 5 Move sample luminaire B away from sample luminaire A and leave the mobile device with the basicDIM wireless app with sample luminaire A. 6 Keep pressing "All luminaires" in the basicDIM wireless app while continuously moving sample luminaire B away from sample luminaire A. 7 Continue with that until sample luminaire B stops responding. => The distance at which this happens is the maximum range. ... At a Glance - Radio technology in lighting applications | 05-2022 | 1.2 | en Influence of the spatial conditions on the luminaire c 29 / 30 "Island problems" must be solved, otherwise the network will never function properly. The following actions can be taken to fix the "island problem". ... Use of repeaters_ Split network into smaller individual networks_ Keep the distance between the as short as possible (less than the maximum range of a )luminaires luminaires _ At a Glance - Radio technology in lighting applications | 05-2022 | 1.2 | en Explanations of used terms and abbreviations c 30 / 30 Bluetooth: Bluetooth is an industry standard for data transmission between devices over short distances using radio technology. The name "Bluetooth" is derived from the Danish King Harald Bluetooth, who united warring parts of Norway and Denmark. Homepage: https://www.bluetooth.com/ _ Thread: Thread is an IPv6-based, low-power mesh networking technology for IoT products, intended to be secure and future- proof. Homepage: https://www.threadgroup.org/ _ WLAN: WLAN (short for Wireless Local Area Network) is a wireless computer network that links two or more devices using wireless communication to form a local area network within a limited area such as a home, school, computer laboratory, campus, or office building. _ ZigBee: ZigBee is a specification for wireless networks with low data traffic such as home automation, sensor networks, lighting technology. This allows devices to communicate with each other. Homepage: https://zigbeealliance.org/ _