Using a Logistic map as the chaos generator, the BER is derived in terms of the signal-to-noise ratios, the number of users and the length of bit sequence. The BER and its upper bound for single-user systems are the special cases of this paper. The calculated BERs are consistent with those found from simulations.

E-cash is essentially a string of bit sequence,which is easy to be copied. The key concern of E-cash is how to effectively prevent E-cash from being double-spent under preconditions that a legal user's anonymity is well protected.

The measured rms jitter of output signal via on-wafer testing is 2.2 ps under the stimulation of 231-1 bit-long pseudo random bit sequence (PRBS) at the bit rate of 11.6 GHz.

The measured rms jitter of recovered clock signal is 4. 7 ps under the stimulation of a 2-1-bit-long pseudorandom bit sequence at the bit rate of 5 Gb/s.

A single channel DR circuit was fabricated in TSMC’s standard 0.18μm CMOS process. The chip area is 0.46mm2.With a 231-1 pseudorandom bit sequence (PRBS) input,the RMS jitter of the recovered 2.5Gb/s data is 3.3ps.

The measured rms jitter of recovered clock signal is 4.7ps under the stimulation of a 211-1-bit-long pseudorandom bit sequence at the bit rate of 5 Gb/s.

The measured rms jitter of recovered clock signal of CRC is 1.6ps under the stimulation of a 223-1-bit-long pseudorandom bit sequence at the bit rate of 8.2 Gb/s.

The bit sequence on the incoming wavelength is converted alternatively to different wavelengths.

A bit error rate of 10-9 is measured at 1 Gbps with nonreturn to zero pseudorandom bit sequence (215-1) at a received optical power of -19 dBm.

Simulation results of non-return-to-zero (NRZ) pseudorandom bit sequence (27-1 code) at 10, 50, and 200-Gbit/s rates of conversion in an ultra-small silicon-on-insulator waveguide are presented.

They claimed to save a factor of two by proposing to divide the packets into halves, routing the first half forward and the second half backward in the bit sequence.

In the theory of stream ciphers, important measures to assess the randomness of a given bit sequence are the linear and the jump complexity, both obtained from the continued fraction expansion (c.f.e.) of the generating function of the sequence.

In this paper,the effects of statistical characteristics of the binary sequence to be transmitted(i.e.line sequence)on the design of the line system are analyzed in connection with the line codes used in secondary group PCM,and the definite restrictions on these statistical cha- racteristics are specified.Then,the pulse density of the binary sequence from the 8448 kb/s digital multiplex equipment using 2048 kb/s primary group PCM is estimated,and the quasi-bit sequence independence of 8448 kb/s digital...

In this paper,the effects of statistical characteristics of the binary sequence to be transmitted(i.e.line sequence)on the design of the line system are analyzed in connection with the line codes used in secondary group PCM,and the definite restrictions on these statistical cha- racteristics are specified.Then,the pulse density of the binary sequence from the 8448 kb/s digital multiplex equipment using 2048 kb/s primary group PCM is estimated,and the quasi-bit sequence independence of 8448 kb/s digital channel is definitely described.Finally,it is indicated that an 8448 kb/s digital channel can be made to have the desirable quasi-bit sequence indepedence by adopting a selfsynchronizing scrambler with suitable number of stages.

This paper presents a hardware-based approach for generating the m random sequence, taking advantage of characteristics possessed by this sort of sequence. The generating rate is hign. For example, for a 16-bit sequence, the rate is 50MHz/ 16=3.125MHz. Moreover, the period of sequence is long, For instance, with the use of a 24-order shift register, the period of a 16-bit sequence is at least 2~(24)/16=2~(20). Hence the pseudo-random number generated in this way can reappear. Since this method...

This paper presents a hardware-based approach for generating the m random sequence, taking advantage of characteristics possessed by this sort of sequence. The generating rate is hign. For example, for a 16-bit sequence, the rate is 50MHz/ 16=3.125MHz. Moreover, the period of sequence is long, For instance, with the use of a 24-order shift register, the period of a 16-bit sequence is at least 2~(24)/16=2~(20). Hence the pseudo-random number generated in this way can reappear. Since this method is implemented completely by hardware, the generating rate is high; the period is long, while CPU and memory arc not occupied. After the uniform distribution test and independence test, it is proven that the random sequence generated in the presented way is a good approximation of an ideal random sequence.

Most of digital watermarks used now are one-dimensional or two-dimensional pseudorandom sequences. These watermarks have some shortages such as with less information and visually meaningless. So watermark images with more information and good perception are more attractive. However, this type of watermark has too much data payload, which limits its applications. In this paper, we use grayscale image instead of binary image as the watermark image, which is visually meaningful but with more difficulty in...

Most of digital watermarks used now are one-dimensional or two-dimensional pseudorandom sequences. These watermarks have some shortages such as with less information and visually meaningless. So watermark images with more information and good perception are more attractive. However, this type of watermark has too much data payload, which limits its applications. In this paper, we use grayscale image instead of binary image as the watermark image, which is visually meaningful but with more difficulty in its implementation. To deal with the huge amount of data introduced, image preprocessing is adopted before embedding process, in which the watermark image is first decomposed using two layer wavelet transformation and a simple and effective affine technique is used to further decompose the coefficients into bit sequences. By controlling the affine parameter, watermark sequence with less data payload can be obtained. The coarse coefficients and detail coefficients are processed separately with different affine parameter so that the quality of the recovered watermark image can be preserved. To balance the relationship between watermark robustness and imperceptibility, the watermark sequences are embedded into wavelet coefficients of original image with properly selected power control factors. By analyzing the contribution of the bits in different sequences and different position, two conclusions are obtained: (1) coarse watermark sequence is much more important for the reconstruction of watermark image than detail watermark sequence; (2) the significance of different bits in one coefficient is also different. Based on them, we propose a novel adaptive embedding strategy, in which coarse and detail watermark sequences are embedded into coarse and detail coefficients of original image, respectively, and each bit is embedded by its significance order. Experimental results show that the proposed technology can reduce the data payload of grayscale watermark greatly. The watermarked image has good perceptual quality. The recovered watermark image has good quality even under JPEG compression with a quality factor of 30. For other distortions such as Additive White Gaussian Noise (AWGN), image resizing and media filtering, the quality of recovered watermark image is also satisfying. Comparison with common algorithm is shown to demonstrate the effective of adaptive embedding strategy.