User's Manual Part 1

3: Detailed Description
APCD-LM043-8.0 (DRAFT C) 35
3.5 CCU–EUM Interface Physical Layer (DSSS Radio)
This section provides a detailed technical description of following aspects of the CCU–EUM
Interface Physical Layer (DSSS Radio):
• Frequency Band on page 35
• Channel Bandwidth on page 35
• Channels on page 36
• Modulation on page 36
• Data Rate on page 37
• Co-located Channels on page 37
• Duplexing on page 37
• Transmit Power on page 38
• Receive Sensitivity on page 38
• Antenna Connector on page 38
• Antenna Control (EUM) on page 38
• Propagation Path on page 38
3.5.1 Frequency Band
The LMS4000 900 MHz Radio Network operates in the 902-928 MHz Industry, Scientific, and
Medical (ISM) frequency band.
3.5.2 Channel Bandwidth
The channel bandwidth is 6 MHz. This channel bandwidth is used to determine the lowest and
highest allowable channel in the band. As illustrated in Figure 22, the center frequency of the
lowest and highest channels have to be set such that the signal power that falls in the bands