Most of the applications in image analysis are based on Freeman chain code. In this paper, for the first time, vertex chain code (VCC) proposed by Bribiesca is applied to improve length estimation of the 2D digitized curve. The chain code has some preferences such as stable in shifting, turning, mirroring movement of image and has normalized starting point. Due to the variety of length estimato...

We introduce a novel scheme for spread spectrum systems, which we call the offset code spreading scheme. By employing the scheme, we can implement a directconversion receiver for a differential-binary phase shift keying system with a DC-cut high pass filter. This will allow us to eliminate the DC-offset by carrier leakage and mitigate the 1/f noise of the mixer. System simulations show that a 1...

Sparsely spread code division multiple access (SCDMA) is a non-orthogonal superposition coding scheme that permits a base station simultaneously communicates with multiple users over a common channel. The detection performance of an SCDMA system is mainly determined by its signature matrix, which should be sparse to guarantee large Euclidean distance for the equivalent signal constellation afte...

We consider a gas of trapped Cooper-paired fermionic atoms that are manipulated by laser light. The laser induces a transition from an internal state with large negative scattering length ~superfluid! to one with weaker interactions ~normal gas!. We show that the process can be used to detect the presence of the superconducting order parameter. Also, we propose a direct way of measuring the siz...

We compare single user digital multi-carrier spread spectrum (MC-SS) modulation with direct sequence (DS) SS (with a modified implementation) in the presence of narrowband interference (NBI) and multipath fading. We derive closed-form expressions for the symbol error probability for both the linear MMSE receiver as well as the conventional matched-filter receiver under different scenarios: addi...

Code Division Multiple Access (CDMA) and multiple input multiple output(MIMO-) CDMA systems suffer from multiple access interference (MAI) which limits the spectral efficiency of these systems. By making these systems more power efficient, we can increase the overall spectral efficiency. This can be achieved through the use of improved modulation and coding techniques. Conventional MIMO-CDMA sy...

We describe a class of parameterized reversible variable length codes that have length distributions identical to Golomb-Rice codes and exp-Golomb codes. The pdfs to which these codes correspond are well matched to statistics of image and video data, thus enabling an increase in robustness to channel errors with no penalty in coding e ciency. These codes are applicable to MPEG-4 and other algor...

Using asymptotic analysis, we study the effect of frequency-flat fading on code division multiple access (CDMA) systems with linear receivers and random spreading sequences. Specifically, we let the number of users grow without bound, while the ratio of number of users to spreading sequence length is kept fixed to a value . We treat separately the cases of slow fading (nonergodic channel) and o...