We introduce a family of directed geometric graphs, denoted \paz, that
depend on two parameters λ and θ. For 0≤θ<2π and 1/2<λ<1, the \paz graph is a strong
t-spanner, with t=(1−λ)cosθ1. The out-degree of a node
in the \paz graph is at most ⌊2π/min(θ,arccos2λ1)⌋. Moreover, we show that routing can be
achieved locally on \paz. Next, we show that all strong t-spanners are also
t-spanners of the unit disk graph. Simulations for various values of the
parameters λ and θ indicate that for random point sets, the
spanning ratio of \paz is better than the proven theoretical bounds