FreeWave Technologies Inc. AMI0032AT 사용자 설명서

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 Spread Spectrum Wireless Data Transceiver User Manual 
Preliminary GXM Manual 
Version 0.2 
35 
PRELIMINARY 
A
NTENNA 
R
EFLECTED 
P
OWER
 
This is a measurement of the transmitted power that is reflected back into the transceiver from 
mismatched antennas or cables, or loose connections between the transceiver and antenna.  A reading 
of 0-5 is good; 5-20 is marginal; 20+ indicates that the connections should be inspected for loose 
connections and cable quality. 
T
RANSMIT 
C
URRENT 
(
M
A) 
This measures the current draw of the transmitter in milliamps.  Refer to Transceiver specs for typical 
values. 
A
VERAGE 
N
OISE 
L
EVEL
 
The average noise level indicates the level of background noise and interference at this transceiver and 
at each of the Repeaters in the link. The number is an average of the noise levels measured at each 
frequency in the transceiver’s frequency hop table. The individual measurement values at each frequency 
hop channel are shown in the frequency table. Pressing the Enter key when the Radio Statistics menu is 
displayed, accesses the frequency table. 
Ideally, noise levels should be below 70 J units and the difference between the average signal level and 
average noise level should be 30 or more. Noise levels significantly higher than this are an indication of a 
high level of interference that may degrade the performance of the link.  High noise levels can often be 
mitigated with band pass filters, antenna placement or antenna polarization.  
A
VERAGE 
S
IGNAL 
L
EVEL
 
The average signal level indicates the level of received signal at this transceiver and at each of the 
Repeaters in the link. For each of these, the signal source is the transceiver that transmits to it. The 
number is an average of the received signal levels measured at each frequency in the transceiver's 
frequency hop table. The individual measurement values at each frequency hop channel are shown in the 
frequency table. Pressing the Enter key when the Radio Statistics menu is displayed accesses the 
frequency table. For a reliable link, the margin should be at least 30 J units. Low Average Signal Levels 
can often be corrected with higher gain antennas, better antenna placement and/or additional Repeaters.  
Note:
  Please consult the install manual for antenna and FCC requirements. 
O
VERALL 
R
CV 
R
ATE 
(%) 
The Overall Receive Rate measures the percentage of data packets that were successfully transmitted 
from the Master to the Slave on the first attempt.  A number of 75 or higher indicates a robust link that will 
provide very good performance even at high data transmission rates. A number of 15 or lower indicates a 
weak or marginal link that will provide lower data throughput. An Overall Receive Rate of 100% will 
provide approximately 100 KBaud of bandwidth with an RF Data Rate setting of 3 and approximately 150 
KBaud of bandwidth with an RF Data Rate of 2. These numbers are reduced approximately 50% if one or 
more Repeaters are in the network. 
R
ADIO 
T
EMPERATURE
 
The Radio Temperature value is the current operating temperature of the transceiver in degrees Celsius. 
For proper operation, a FreeWave transceiver must be in the temperature range of -40° to +75° C. Some 
of the transceivers are only tested down to 0° C. See transceiver specification papers for details.