User Guide: Technical Reference
SECTION 2
ioLink 4
SYSTEM COMPONENTS
PRELIMINARY
Customer Support (202) 333-7031
2-8
The
ioLink 4
provides full-duplex communications – both ends of the link can transmit and receive signals
simultaneously, which enables real time voice, video, and data communications. The diagram below
shows a typical setup.
Antenna
User
Equipment
Full-Duplex
Spread Spectrum
Communication Link
RF U nit
RF U nit
Modem
Unit
Modem
Unit
One communications link consists of one
ioLink 4
terminal (RF Unit, Modem Unit, Antenna, and Cables)
installed at each end of the line-of-sight link. Once the link is established between the two terminals:
1. The sending user’s data is fed through the modem where it is multiplied by a pseudo-
random noise (PN) code to spread the signal. It is then connected to a 110 MHz Intermediate
Frequency (IF) and sent to the RF unit.
2.
The IF signal is further upconverted to a 2.4 GHz RF, or a 5.7 GHz RF, and is passed through a
series of filters and amplifiers and transmitted via the antenna to the other end of the link. There,
the information goes to the receiving user’s device by reversing the process used on the transmit
side.
2.7.1 Normal Operation
Figure 2-5. Typical Link Diagram
Destination
User
Source
