By combining the design of safeguard zone and traditional time-hopping (TH) sequences,we construct a class of TH sequences with two-stage few-hit zone (FHZ) suitable for quasi-synchronous time-hopping spread spectrum ultra wideband (QS-THSS-UWB) systems.

We find that, in certain coupling schemes (for example, the variable y driving x in the Lorenz system) and under proper coupling strengths, a nonlocal approximate synchronization happens between the first and the third oscillator, or all succeeding ones, which are not directly connected, accompanied with a desynchronization between the first and the closest, namely the second one.