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.
We report a system-on-chip (SoC) realised in 130nm CMOS for implantable telemetry systems and mobile health applications featuring 6 neural stimulation channels and acquisition circuits for 9× electrode-based recordings (ExG), 4×/32× photo-plethysmography (PPG), bio-impedance, and temperature. The SoC includes a low-power quad-core processor (34μW/MHz) with sophisticated power and clock management...
In this paper, we study a novel optical orthogonal frequency division multiplexing (OFDM) scheme, fractional reversed polarity optical OFDM (FRPO- OFDM), which enables dimmable visible light communications. The scheme combines an asymmetrically clipped optical OFDM (ACO-OFDM) sequence with an information-carrying brightness control sequence (BCS). We show that the new scheme can create a wide range...
Visible light positioning (VLP) for indoor applications has recently received considerable attention. In this paper, an aperture based receiver is considered and the position is estimated based on the angle-of-arrival (AOA), because the AOA can be determined by comparing the relative differences in the received signal strengths (RSS) in the different photodiodes (PDs) of the receiver. Hence, in contrast...
In this paper, we investigate the problem of indoor positioning using visible light systems. The directional detector array we use is comprised of a number of receiving elements, each consisting of an aperture and a photo diode, which are arranged to offer good angular diversity, and can be implemented within a compact receiver structure [1]. The receiving elements receive the light from a number...
This paper describes the use of an optical receiver which has photodiodes (PDs) with two different fields of view (2-FOV) in an indoor visible light communications (VLC) system. Data is transmitted using asymmetrically clipped optical OFDM (ACO-OFDM) from white light emitting diodes (LEDs) which are also used for illumination. A cellular configuration is considered where each transmitter transmits...
In this paper, a prism array-based receiver for intensity-modulated direct-detection (IM/DD) optical wireless systems has been investigated. The receiver uses an array of prisms to achieve angular diversity within a compact receiver structure. The transmission of light through a prism onto a photodetecting surface is presented, showing the power loss of the light. The resulting channel gains are determined...
We show that the performance of InGaN/GaN axial nanowire LEDs is largely limited by the poor carrier injection efficiency. We have further demonstrated high performance phosphor-free white LEDs using InGaN/GaN/AlGaN dot-in-a-wire core-shell heterostructures.
White lighting LED based systems are emerging as an important form of high data rate communications, especially for indoor applications. Two limitations of existing systems are the small field of view of typical receivers and the poor performance of optical wireless MIMO due to lack of spatial diversity. In this paper we describe a novel design which overcomes these problems by using a hemispherical...
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.