Recent Patents on Signal Processing (Discontinued) - Volume 2, Issue 1, 2012

In this issue of the journal of Recent Patents on Signal Processing we present another set of interesting research and overview papers giving the readers a glance on the multidisciplinary nature of applied aspects involved in the field of signal processing. Specifically this issue presents seven papers. One of the papers deals with vision and image processing. The authors show that the non-linear nature of the human visual resp Read More

INTRODUCTION Optical signal processing is a quite wide area with the combination of optoelectronic technologies and signal processing technologies. It deals with the various optical signal operations including optical logical operation [1], imaging [2, 3], encoding and decoding [4], data transmission and exchange [5], encryption [6], etc. Owing to the advantages of high-speed and high-capacity signal processing abil Read More

Terahertz radiation (0.1-10 THz) sits in the electromagnetic spectrum between microwave and mid infrared region. Imaging technologies utilizing this frequency range have recently attracted interests of many scientists considering their potential applications in various areas, such as non-invasive security screening, chemical identification, pharmaceutical and biological sensing. In this paper, we review recent advances an Read More

There is currently a great deal of interest in the development of efficient compact sources of terahertz (THz) radiation. There are many factors of device and materials design which are still under ongoing improvement with the aim of producing an efficient, high power, room-temperature THz signal emission device which is tunable over a practical THz frequency range. The recent advances in production of various room-tempe Read More

Optical systems as information processing systems have become quite impressive recently in optical image encryption and watermarking. Benefits of optical systems over the electronic counterparts are that optical processing provides the maximum number of degrees of freedom, and that optical encryption is ideal for information stored in holographic media. Various schemes have been proposed in the last decade. In this a Read More

The non-linear nature of the human visual response to achromatic contrast is a key element to improve the performance in achromatic image coding. Expressing transform coefficients in the appropriate contrast units is relevant when some particular non-linear processing hasto be applied. In the achromatic case, the use of non-linear psychophysical models is straightforward since achromatic contrast computation from ima Read More

ATM, SDH or satellite have been used in the last century as the contribution network of Broadcasters. However the attractive price of IP networks is changing the infrastructure of these networks in the last decade. Nowadays, IP networks are widely used, but their characteristics do not offer the level of performance required to carry high quality video under certain circumstances. Data transmission is always subject to errors on li Read More

Recently, orthogonal frequency division multiplexing (OFDM) has been adopted as the standard of the next generation mobile networks. We proposed the several transmission techniques in the patents. OFDM allows only one user on the channel at any given time. To accommodate multiple users, orthogonal frequency division multiple access (OFDMA) has been proposed. In the conventional OFDM systems, large pilo Read More

This article focuses on the realization of all-optical signal processing functions based on the nonlinearities of a semiconductor optical amplifier (SOA) by reviewing the recent and significant patents and publications related to these new developments and applications. One of the main contributions of this paper is to highlight the feasibility of experimental implementation of three logic gates: NAND, OR, and NOR optical Read More

The patents annotated in this section have been selected from various patent databases. These recent patents are relevant to the articles published in this journal issue, categorized by the processes and technologies related to various disciplines of signal processing sciences.