Abstract A new multicarrier multi-rate digital demultiplexer system structure based on MF-TDMA(Multi-Frequency Time Division Multiple Access) in a wideband satellite communication is described. Compared with the traditional tree method, uses half-band filter instead of quadrature mirror filter, which has three advantages: 1) It fully avoids shortcomings such as confusion distortion and amplitud...

Satellite image Security is playing a vital role in the field of communication system and Internet. This work is interested in securing transmission of Meteosat images on the Internet, in public or local networks. To enhance the security of Meteosat transmission in network communication, a hybrid encryption algorithm based on Advanced Encryption Standard (AES) and Rivest Shamir Adleman (RSA) al...

We investigate the issue of global energy efficiency optimization in a multi-beam low Earth orbit (LEO) satellite communication system. Current terrestrial networks provide high-quality and cost mainly densely populated areas. However, extending wideband coverage to remote areas is unaffordable. LEO satellites solution for offering by supporting networks. consider downlink transmissions Ka-band...

In this article, a multiport beamforming system based on the reconfigurable waveguide phased antenna array is presented, which fed by microstrip single-layer feeding network. The transitions and linear-polarized/circular-polarized arrays have high flexibility to meet different requirements in applications according design purposes, also suitable for satellite communication with separate transmi...