VSAT Satellite Communication Systems

Информация

EvmarSAT Satellite Communication System uses several unique modern technologies, providing the most efficient satellite bandwidth utilization and flexibility, and offering the broadband service of highest quality. Due to use of these advanced technologies, EvmarSAT occupies the leading position at the market of broadband satellite communication.

EvmarSAT provides two-way transparent IP connectivity, using jitter-free Dynamic BoD BM-FDMA (Bandwidth on Demand with Burst Mode Frequency Division Multiple Access) technology for inbound channels.

Отличительные Особенности

Differences between MF-TDMA and Dynamic BoD BM-FDMA Technologies

MF-TDMA Technology

Single channel demodulators process inbound channels with predefined central frequencies and fixed bandwidths, divided to predetermined time intervals and shared between multiple VSATs.
The system allocates several VSATs to an inbound channel with fixed bandwidth. Each of these VSATs can transmit on this channel only within short separated intervals (timeslots). That unavoidably introduces additional variable delay (Jitter) to packets transfer.
Time synchronization of all VSATs transmissions is required.
Outdoor units (BUC and antenna) must be identical for all VSATs and designed to support transmission rate of the widest channel in the system.

Dynamic BoD BM-FDMA Technology

Multichannel demodulators process the whole bandwidth, shared between all currently transmitting VSATs and allocated for dynamically changing by their widths and central frequencies inbound channels.
Upon receiving request from a VSAT, the system immediately allocates to it a dedicated channel for transmission with the necessary, dynamically changing on demand bandwidth and center frequency within the range assigned for all inbound channels. That guaranties jitter-free packets transfer.
No need for time synchronization.
Outdoor unit (BUC and antenna) is selected individually for each VSAT in accordance with maximum data rate assigned to it. This reduces the Outdoor unit size and cost.