Amplified Recirculating Delay Lines as Fiber-optic Decoders in TV Systems

A novel approach to decoding chrominance signal in amplitude-modulated vestigial-sideband (AM-VSB) television systems is described. The decoding scheme is achieved by means of amplified recirculating delay lines as fiber-optic filters. The technique is experimentally verified by decoding the chrominance components of the UHF channel 21 of G PAL standard.Publicad

Waveguide manufacturing technologies for next-generation millimeter-wave antennas

International audienceSome recent waveguide-based antennas are presented in this paper, designed for the next generation of communication systems operating at the millimeter-wave band. The presented prototypes have been conceived to be manufactured using different state-of-the-art techniques, involving subtractive and additive approaches. All the designs have used the latest developments in the field of manufacturing to guarantee the required accuracy for operation at millimeter-wave frequencies, where tolerances are extremely tight. Different designs will be presented, including a monopulse antenna combining a comparator network, a mode converter, and a spline profile horn; a tunable phase shifter that is integrated into an array to implement reconfigurability of the main lobe direction; and a conformal array antenna. These prototypes were manufactured by diverse approaches taking into account the waveguide configuration, combining parts with high-precision milling, electrical discharge machining, direct metal laser sintering, or stereolithography with spray metallization, showing very competitive performances at the millimeter-wave band till 40 GHz. © 2021 by the authors. Licensee MDPI, Basel, Switzerland