Definitions - Motorola PTP 300 Series User Manual

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6.1.4 Definitions
The equipment capability is given in Table 7, Table 9 (IP Mode) and Table 8, Table 10 (TDM
Mode). Each table gives Maximum typical Link Loss, Output Power and System Thresholds for
PTP 300 Series Bridge in all modulation modes.
Adaptive Modulation will ensure that the highest throughput that can be achieved instantaneously
will be obtained taking account of propagation and interference. The calculation of Equation (3)
needs to be performed to judge whether a particular link can be installed. When the link has been
installed, web pages provide information about the link loss currently measured by the equipment
both instantaneously and averaged. The averaged value will require maximum seasonal fading to
be added, and then the radio reliability of the link can be computed.
For minimum error rates on TDM links the maximum modulation mode should be limited to
64QAM and channel coding rate of R= 0.75, denoted as 64QAM 0.75..
The values for BPSK are static Receive Sensitivity measurements. The other values are static
Receive Sensitivity measurements with an AMOD threshold applied. The AMOD threshold applied
is for a benign radio channel.
Sensitivity: Sensitivity is defined as the combined receive input signal level on both horizontal
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and vertical inputs that produces a Null Bit Error Ratio of 3x10 .
Output Power: The output power is for a centre channel in Region 1. The output power will be
reduced on the edge channels and may vary if different region codes are selected.
AMOD Threshold: The AMOD threshold is the combined receive input signal level on both
horizontal and vertical inputs that results in the link consistently entering the receive modulation
mode under consideration as the signal level is increased.
System Threshold: Thresholds for all modes except BPSK are for the relevant link optimization
AMOD thresholds. System threshold for BPSK is the BPSK receive sensitivity.
Maximum Link Loss: The maximum link loss for each modulation mode is derived from the
AMOD threshold for that mode (sensitivity threshold for BPSK) and the maximum Region 1
centre channel output power. The figures assume integral antennas with 23dBi (5.8 GHz and 5.4
GHz) gain are used.
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