In Ultra-wideband (UWB) system mainly coexisting with other narrow band systems, a judicious pulse shape design is necessary, under the IEEE 802.15.4a standard and the Federal Communications Commission (FCC) spectral mask constraints. In this letter, a strategy to generate multiple orthogonal pulses while complying with both constraints is presented. The performance analysis is also presented with mathematical derivations and numerical simulations to show that the proposed pulses can be utilized for higher data rate or lower error rate.