Westell Inc. CSI-DSP85-PSS8 ユーザーズマニュアル
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Accurate attenuator values need to be chosen to ensure that the maximum total power (higher of Composite or In-Band Input)
applied to the donor and server port(s) does not exceed the following thresholds:
applied to the donor and server port(s) does not exceed the following thresholds:
Input Signal
Max Gain
Input Signal
Max Gain
<-55 dBm
85 dB
-39 dBm
69 dB
-54 dBm
84 dB
-38 dBm
68 dB
-53 dBm
83 dB
-37 dBm
67 dB
-52 dBm
82 dB
-36 dBm
66 dB
-51 dBm
81 dB
-35 dBm
65 dB
-50 dBm
80 dB
-34 dBm
64 dB
-49 dBm
79 dB
-33 dBm
63 dB
-48 dBm
78 dB
-32 dBm
62 dB
-47 dBm
77 dB
-31 dBm
61 dB
-46 dBm
76 dB
-30 dBm
60 dB
-45 dBm
75 dB
-29 dBm
59 dB*
-44 dBm
74 dB
-28 dBm
58 dB*
-43 dBm
73 dB
-27 dBm
57 dB*
-42 dBm
72 dB
-26 dBm
56 dB*
-41 dBm
71 dB
-25 dBm
< 55 dB*
-40 dBm
70 dB
*We recommend padding this level due to potential for fluctuating signal.
-25 dBm is the maximum input signal level that should be applied to the repeater, even if the gain is lower than 55 dB.
Input signals exceeding these thresholds will result in composite input attenuation, called “ADC Protect” (Analog to Digital Converter
Protection). Output power is reduced whenever the above thresholds are exceeded by reducing the gain by 1dB for each 1 dB that
the threshold is exceeded. ADC Protect should not be confused with AGC (Automatic Gain Control), which reduces gain to prevent
In-Band (measured) output power from exceeding the specified maximum output level. To determine the total power applied to the
donor and server ports, please reference the “Composite Input” values as reported in the Web (“System Status”) or Menu (“Link
Status”) interfaces (depicted and explained later in this manual).
Input signals exceeding these thresholds will result in composite input attenuation, called “ADC Protect” (Analog to Digital Converter
Protection). Output power is reduced whenever the above thresholds are exceeded by reducing the gain by 1dB for each 1 dB that
the threshold is exceeded. ADC Protect should not be confused with AGC (Automatic Gain Control), which reduces gain to prevent
In-Band (measured) output power from exceeding the specified maximum output level. To determine the total power applied to the
donor and server ports, please reference the “Composite Input” values as reported in the Web (“System Status”) or Menu (“Link
Status”) interfaces (depicted and explained later in this manual).
Large delta’s between in-band and composite input signals:
Care should be taken to isolate the best donor site to ensure the least possible delta between in-band and composite downlink
signals. If the (downlink) composite input exceeds the in-band input by more than 3 dB for the SMR band the maximum output power
will be reduced. Example:
Band (SMR)
In-Band Input -45 dBm
Composite Input -38 dBm
Max Gain = 68 dB
Max Output = 23 dBm
Care should be taken to isolate the best donor site to ensure the least possible delta between in-band and composite downlink
signals. If the (downlink) composite input exceeds the in-band input by more than 3 dB for the SMR band the maximum output power
will be reduced. Example:
Band (SMR)
In-Band Input -45 dBm
Composite Input -38 dBm
Max Gain = 68 dB
Max Output = 23 dBm
TO INSIDE ANTENNA
TO OUTSIDE ANTENNA
1:1 PORT CONFIGURATION
STANDARD MODEL
Input: One single band port, from the single band donor.
Output: One single band port to the DAS.
Attenuator Selection Guidelines: