Iet Optoelectronics 

About: Iet Optoelectronics is an academic journal published by Institution of Engineering and Technology. The journal publishes majorly in the area(s): Laser & Bit error rate. It has an ISSN identifier of 1751-8768. It is also open access. Over the lifetime, 675 publications have been published receiving 6900 citations. The journal is also known as: Institution of Engineering and Technology optoelectronics & Optoelectronics.

Free-space optical communication employing subcarrier modulation and spatial diversity in atmospheric turbulence channel

Abstract: An expression for the bit error rate of a multiple subcarrier intensity-modulated atmospheric optical communication system employing spatial diversity is derived. Spatial diversity is used to mitigate scintillation caused by atmospheric turbulence, which is assumed to obey log-normal distribution. Optimal but complex maximum ratio, equal gain combining (EGC) and relatively simple selection combining spatial diversity techniques in a clear atmosphere are considered. Each subcarrier is modulated using binary phase shift keying. Laser irradiance is subsequently modulated by a subcarrier signal, and a direct detection PIN receiver is employed (i.e. intensity modulation/direction detection). At a subcarrier level, coherent demodulation is used to extract the transmitted data/information. The performance of on-off-keying is also presented and compared with the subcarrier intensity modulation under the same atmospheric conditions.

Generic foundry model for InP-based photonics

Abstract: Similarities and differences between photonic and microelectronic integration technology are discussed and a vision of the development of InP-based photonic integration in the coming decade is given.

Performance enhancement of outdoor visible-light communication system using selective combining receiver

Abstract: New generation of high-intensity aluminium gallium arsenide (AlGaAs) and aluminium indium gallium phosphide (AlInGaP) light-emitting diodes (LEDs) which have permitted the replacement of incandescent-based traffic lights with LED-based traffic lights, unfolds the potential of implementing visible-light communication (VLC) system on outdoor environment. The feasibility of outdoor VLC system is undoubtedly questionable because of the significant ambient-light noise caused by daylight. Existing performance studies related to this system have not taken into account the effect of ambient-light noise which varies largely from day time to night time. The authors propose an analytical daylight noise model based on a modified Blackbody radiation model to capture the effect of ambient-light noise and conduct an in-depth study on the impact of daylight on the system performance. The proposed daylight noise model allows us to perform analytical analysis which produces relatively accurate results with less complexity, as compared to the existing time-consuming simulation. The authors also introduce a new receiver structure employing the selective combining technique to significantly reduce the effect of background noise. From numerical analysis, the authors show that the new receiver structure is able to achieve a signal-to-noise ratio (SNR) improvement of approximately 5 dB and establish a stable communication link at any time of the day.

Proposal for 4-to-2 optical encoder based on photonic crystals

Abstract: In this study, an all optical 4-to-2 encoder have been proposed which has four input and three output ports. The proposed structure can generate a 2-bit binary code considering which input port is active. For realising the proposed structure first the authors proposed and designed a BUFFER and an OR gate. Then combined these basic gates to realise the proposed encoder. The maximum switching delay and footprint for the proposed structure are about 200 fs and 880 μm2, respectively.

Survey on optical camera communications: challenges and opportunities

Abstract: Wireless technologies based on radio frequencies (RFs) have always dominated other types of wireless technologies up until now. However, the recent proliferation of media-rich smart devices has pushed the RF spectrum usage to its limit. Therefore RF band expansion towards the optical spectrum is imminent in commercial scale. Indeed, the research on wireless communications using the optical spectrum has gained tremendous ground during the past couple of decades and standardised, respectively, by infrared data association for infrared communication and IEEE 802.15.7 for visible light communication. However, only few shortcomings of the IEEE 802.15.7 standard have led to the development of a revised version, called IEEE 802.15.7r1. This article provides an insight on the activity of the proposed revision of IEEE 802.15.7r1. The proposed revision version targets communication systems that mainly use either image sensors or cameras, known as the optical camera communications (OCC). Leveraging the existing infrastructure, OCC systems will be able to provide ubiquitous coverage in both indoors and outdoors. The authors present their survey focusing on the key technology consideration in IEEE 802.15.7r1, current research status, impairments, enhancements and futuristic application scenarios of the OCC systems.