The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
For LED-based transmitters used in optical wireless transmissions, the relationship between the input voltage and the output light intensity of an LED is nonlinear. Hence, voltage modulation cannot be used directly on an LED for continuous modulation such as OFDM without signal distortion. Compared to voltage modulation with a predistortion circuit, current modulation is simpler to apply since the...
Light Emitting Diodes (LEDs) have a wide range of applications, including illumination and data transmission in Optical Wireless Communications (OWC) systems. Analog modulation used in Orthogonal Frequency Division Multiplexing (OFDM) to overcome Inter-Symbol Interference (ISI) suffers from significant nonlinear distortion when voltage modulation is applied to LEDs. We investigate and analyze current...
We develop a prototype to demonstrate indoor wireless visible light communications (VLC) in which a panel of red, green, and blue (RGB) light-emitting diodes (LEDs) is used as a transmitter as well as a light source. Digital transmissions of text messages are carried out from the LED panel mounted on top of the room ceiling to the receiver located on the table top 2 m vertically below. Using low-cost...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.