Understanding IDR: Intermediate Data Rate for Satellite Communication

IDR stands for Intermediate Data Rate, a technology specifically designed to provide E1 connectivity through a satellite network. It operates at a rate of 2.048 Mbps and its multiples.

IDR technology adheres to the standard compliance and performance requirements for IDR carriers as defined by IESS 308/310.

The satellite bandwidth occupied by an IDR carrier is approximately 0.7 times the transmission rate when using QPSK modulation. With 8-PSK modulation, this drops to around 0.467 times the transmission rate.

IDR Equipment

IDR equipment is specialized to support IDR data rates and typically includes:

• Satellite modem
• RF up converter
• RF down converter
• Switch over units
• And other related components

This equipment is generally compliant with all satellite earth stations that operate with INSAT-based systems.

RF Conversion

The RF up converter is responsible for converting the intermediate frequency (IF) in the range of 52-88 MHz to the radio frequency (RF) in the C band range (5.925GHz to 6.425GHz), without frequency inversion.

Conversely, the RF down converter converts the C band RF frequency back to the IF frequency.

Modem Interface and Redundancy

The satellite modem interfaces using baseband and RF. The Modem SWO (Switch Over) unit provides N+1 redundancy, where N can be up to a maximum of 8.

The Up/Down Converter SWO unit offers 1+1 redundancy.

C-DOT IDR Equipment Features

The C-DOT IDR Equipment provides a user interface that supports comprehensive:

• Monitoring
• Diagnostics
• Administrative functions