Abstract The conversion of transverse mode-locked (TML) laser beams from a Hermite-Gaussian (HG) to Laguerre-Gaussian (LG) mode set using cylindrical lens converter was demonstrated experimentally. By changing the spatial symmetry new spatio-temporal dynamics for TML lasers were enabled. In particular, fast linear motion an oscillating spot, generated by based on HG modes, translated into circu...

This paper presents an architecture for multi-mode terminals, strictly speaking multi-mode receivers, exploiting IF sampling with Sigma-Delta ADCs. It is shown that Sigma-Delta ADCs are not only an efficient means of digitizing signals but are a nearly perfect fit to the task of analog-to-digital conversion in multi-mode terminals. For further processing the digitized signal, i.e. channel filte...