Single Channel Imaging Receiver Research Articles

Performance Analysis of QAM with MEMS Based SCIR for Indoor Optical Wireless Communication

This paper presents the systematic evaluation of performance of indoor optical wireless communication using different modulation schemes and micro electro mechanical systems - single channel imaging receiver (MEMS-SCIR). For the future modern world, indoor optical wireless communications (OWC) play a vital role. The main objective is to compare the performance of various modulation schemes in terms of their bit error probability. On -off keying (OOK) and pulse position modulation (PPM) are widely used in optical wireless communication for its simplicity. Here different digital modulation schemes are approached; bit error rate (BER) is calculated over additive white Gaussian noise channel (AWGN). M-quadrature amplitude modulation (MQAM) gives a better BER performance compared to the M- phase shift keying (MPSK). Thus, MQAM based MEMS-SCIR provides better performance in indoor optical wireless communications.

High-Speed Full-Duplex Optical Wireless Communication System with Single Channel Imaging Receiver for Personal Area Networks

In this paper, we propose a high-speed full-duplex optical wireless communication system using a single channel imaging receiver for personal area network applications. This receiver is composed of an imaging lens, a small sensitive-area photodiode, and a 2-aixs actuator and it can reject most of the background light. Compared with the previously proposed system with single wide field-of-view (FOV) non-imaging receiver, the coverage area at 12.5Gb/s is extended by > 20%. Furthermore, since the rough location information of the user is available in our proposed system, instead of searching for the focused light spot over a large area on the focal plane of the lens, only a small possible area needs to be scanned. In addition, by pre-setting a proper comparison threshold when searching for the focused light spot, the time needed for searching can be further reduced. Proof-of-concept experiments have been carried out and the results show that with this partial searching algorithm and pre-set threshold, better performance is achieved.

High-speed indoor optical wireless communication system with single channel imaging receiver: erratum

High-speed indoor optical wireless communication system with single channel imaging receiver: erratum

High-speed indoor optical wireless communication system with single channel imaging receiver

In this paper we experimentally investigate a gigabit indoor optical wireless communication system with single channel imaging receiver. It is shown that the use of single channel imaging receiver rejects most of the background light. This single channel imaging receiver is composed of an imaging lens and a small photo-sensitive area photodiode attached on a 2-axis actuator. The actuator and photodiode are placed on the focal plane of the lens to search for the focused light spot. The actuator is voice-coil based and it is low cost and commercially available. With this single channel imaging receiver, bit rate as high as 12.5 Gbps has been successfully demonstrated and the maximum error-free (BER<10⁻⁹) beam footprint is even larger than 1 m. Compared with our previous experimental results with a single wide field-of-view non-imaging receiver, an improvement in error-free beam footprint of >20% has been achieved. When this system is integrated with our recently proposed optical wireless based indoor localization system, both high speed wireless communication and mobility can be provided to users over the entire room. Furthermore, theoretical analysis has been carried out and the simulation results agree well with the experiments. In addition, since the rough location information of the user is available in our proposed system, instead of searching for the focused light spot over a large area on the focal plane of the lens, only a small possible area needs to be scanned. By further pre-setting a proper comparison threshold when searching for the focused light spot, the time needed for searching can be further reduced.

Single-channel imaging receiver for optical wireless communications

A novel and simple single-channel imaging receiver for high-speed portable wireless infrared communications is proposed. The receiver is able to aim automatically at the ceiling areas with better signal-to-noise ratio. The self-orienting capability, together with the very narrow field of view employed, drastically reduces the path loss, background noise and multipath distortion. Moreover, its single-channel structure minimizes hardware complexity in contrast to conventional angle diversity receivers. Our simulation results indicate that the proposed receiver, operating in a multispot diffusing configuration, offers significant gains in power requirements and channel bandwidth compared to angle diversity receivers.