Zhang Li-jun

Anti-interference ultra-wideband system based on spreading and interleaving

To suppress the interference in the ultra-wideband (AI-UWB) system is a challenging problem. An anti-interference multiband orthogonal frequency-division multiplexing ultra-wideband (AI-UWB) system, based on spreading and interleaving is addressed. It will exploit the frequency diversity across the subcarriers and provide the robustness to narrow-band interference, by spreading the coded bit streams within each sub-band and interleaving across all sub-bands. Simulating results show that the spreading and interleaving provide about 5 dB to 10 dB advantages over the conventional multiband orthogonal frequency-division multiplexing ultra-wideband system in signal-to-interference ratio. Spreading and interleaving is an effective cure for enhancing the robustness to narrowband interference.

Verifiable (t, n) threshold signature scheme based on elliptic curve

Based on the difficulty of solving the ECDLP (elliptic curve discrete logarithm problem) on the finite field, we present a (t, n) threshold signature scheme and a verifible key agreement scheme without trusted party. Applying a modified clliptic curve signature equation, we get a more efficient signature scheme than the existing ECDSA (elliptic curve digital signature algorithm) from the computability and security view. Our scheme has a shorter key, faster computation, and better security.AbstractBased on the difficulty of solving the ECDLP (elliptic curve discre logarithm problem) on the finite field, we present a (t, n) threshold signature scheme and a verifiable key agreement scheme without trusted party. Applying a modified clliptic curve signature equation, we get a more efficient signature scheme than the existing ECDSA (elliptic curve digital signature algorithm) form the computability and security view. Our scheme has a shorter key, faster computation, and better security.