Indoor Mobile Optical Wireless Antennas for Portable Devices

A high demand for increasing need for bandwidth and data rates has paved way for optical fiber and optical wireless communications into last mile solutions for optical communications. This dissertation focuses on providing a solution to obtain Optical Wireless (OW) for indoor mobile portable devices. A new optical antenna model is proposed for such portable devices. Optical sweeping in 3D using Acousto Optics Cell Arrays (AOCAs) is proposed. This Opto-electronic method provides better coverage area for Line Of Sight optical link establishment and reconnection. The proposed method also has superior and precise beam divergence manipulation capabilities. Its geometry, coverage area and mobility are analyzed. Indoor dimensions of Height (5m), Width (20m), and Length (20m) are considered. The optical antenna can sweep through the hemispherical shape in the direction of optical beam focal plane using AOCAs. The link budget analysis is done using commercially available component ratings and the optical power for the entire coverage area of the optical antenna is found to be higher than the receiver's minimum sensitivity. The limitations on the nodes such as size and power consumption are studied and the model is designed to run efficiently on power ratings of the portable device battery. The proposed optical antenna can be fabricated in the form of a cube of size 2x2x2 mm. The optical power usage at any given time ranges from 50 mW to 0.5W. The bit error rates from SNR calculations are found to be around 10-10 at data rates of up to 4 Gbps. The Line of Sight (LOS) connection time and reestablishment time ranges from 4 to 7 μs depending on the AOCA process time. VCSEL transceiver optical characteristics are simulated to verify the validity of the model.