In this paper, we propose a new spatial interpolation algorithm for Intra-Frame error concealment. The method aims at interpolating areas in the image, which have been affected by packet loss. We have proposed an edge detection technique to aid the bilinear interpolation. The edgedetection scheme is based on designing a robust Hough transform-based technique that is capable of systematically connecting edges irrespective of the number of edge points surrounding missing areas. The connected edges are used to divide the missing areas into different regions for interpolation along the directions of each detected line. Simulation results demonstrate that the proposed algorithm can recover the missing areas with a greater accuracy, when compared with the bilinear interpolation technique.

Advanced vehicle-based safety and warning systems use laser scanners to measure road geometry (position and curvature) and range to obstacles in order to warn a driver of an impending crash and/or to activate safety devices (air bags, brakes, and steering). In order to objectively quantify the performance of such a system, the reference system must be an order of magnitude more accurate than the sensors used by the warning system. This can be achieved by using high-resolution range images that can accurately perform object tracking and velocity estimation. Currently, this is very difficult to achieve when the measurements are taken from fast moving vehicles. Thus, the main objective is to improve motion estimation, which involves both the rotational and translation movements of objects. In this respect, an innovative recursive motion-estimation technique that can take advantage of the in-depth resolution (range) to perform accurate estimation of objects that have undergone three-dimensional (3-D) translational and rotational movements is presented. This approach iteratively aims at minimizing the error between the object in the current frame and its compensated object using estimated-motion displacement from the previous range measurements. In addition, in order to use the range data on the nonrectangular grid in the Cartesian coordinate, two approaches have been considered: 1) membrane fit, which interpolates the nonrectangular grid to the rectangular grid, and 2) the nonrectangular-grid range data by employing derivative filters and the proposed transformation between the Cartesian coordinates and the sensor-centered coordinates. The effectiveness of the proposed scheme is demonstrated for sequences of moving-range images.

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Joint source-channel coding/decoding (JSCC/JSCD) techniques in flow media communications have become a state-of-the-art and one of the challenging research subjects in the spatial communication area. They have great application prospective and deep impact in various manned space flights, satellite missions, mobile radio communications and deep-space explorations. In the last few years, there have been influential achievements in JSCC/JSCD studies. This paper aims at an introduction to the basic principles of joint source-channel optimal design. A general summarization and classification for various existing JSCC/JSCD methods is addressed. Also presented is a JSCD scheme based on variable-length coding, capable of providing reliable resolutions for flow media data transmission in spatial communications.

In this paper, we have proposed a joint source-channel coding/decoding approach by combining RVLC and VLC for CCSDS IDC coefficients, which can be applied in space communication. In the CCSDS IDC standard, the DC coefficients are given special protection by using a reversible coding/decoding scheme since they are especially significant for the reconstructed image quality. Specifically, the DC coefficients are encoded by reversible variable length codes (RVLCs) after using alternating run-length encoding, which can simplify the code-table design and decrease the decoding complexity by transforming the variable length coded DC coefficients into very few symbols. Simulation results show that this approach can greatly alleviate error propagation and improve the error-resilient performance of the DC coefficients, which can greatly improve the transmitted image quality.

Date of publication xxxx 00, 0000, date of current version xxxx 00, 0000.

Previous research shows that it is possible to achieve fullduplex system as long as self-interference is cancelled enough. Digital cancellation method is an important step to remove the residue self-interference signal in digital domain. Compared with prior art, this paper purposes a novel digital cancellation method. The recursive least squares (RLS) algorithm is introduced and digital filter length can be adjusted adaptively based on the self-interference channel characteristic. The real-time experimental results show that our method has fairly desirable performance than previous research. It can achieve about 26dB for 5MHz bandwidth signal at high transmit power 15dBm. Furthermore, it is still effective when passive and active cancellation mechanisms are not ideal.