User Manual

Table Of Contents
Exalt Installation and Management Guide
ExtendAir (TDD) Series Digital Microwave Radios
203591-002 7
2009-12-18
Pre-installation Tasks
This section describes the steps necessary to prepare a site for the installation of the Exalt Digital
Microwave Radio.
Link Engineering and Site Planning
Design all terrestrial wireless links prior to purchase and installation. Generally, professional wireless
engineering personnel are engaged to determine the viability and requirements for a well-engineered
link to meet the users’ needs for performance and reliability.
Please use the ExaltCalc path calculator, which aids in the pre-planning and engineering required to
determine following attributes:
Antenna type and gain at each end of the link
Antenna mounting height/location for proper path clearance
Antenna polarization orientation
RF cabling type, length, connectors, route, and mounting
Antenna system grounding
Lightning arrestor type(s), location(s), and grounding
Radio mounting location and mechanisms
Radio grounding
Radio transmitter output power setting
Anticipated received signal level (RSL) at each end
Anticipated fade margin and availability performance at each end
Radio settings for TDD frame length and occupied bandwidth
Anticipated throughput performance (TDM circuit support and Ethernet)
Anticipated system latency
With respect to radio path and site planning, these radios are generally identical to other microwave
terrestrial wireless systems. Engineering of these systems requires specific knowledge about the
radios, including:
RF specifications (transmitter output power, receiver threshold, occupied channel bandwidth, and
carrier-to-interference to erance)
Regulatory limitations on transmitter output power setting and antenna type/gain
Noise/interference profile for the intended location
Familiarization with the ExtendAir (TDD) Radios
The ExtendAir (TDD) radios utilize time division duplex (TDD) radio transmission. This means that
the transmitted signal in both directions uses the same center frequency and transmits in one direction
for a period of time, and then in the opposite direction for another period of time. This total period of
time is referred to as the frame length or TDD frame length, and is further discussed in Time Division
Duplex (TDD) Factors.