Alvarion Technologies Ltd. BMAX-BA36 Manuale Utente

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Base Station Equipment
BreezeMAX Modular Base Station System Manual 
11
1.2.7
Power Interface Unit (PIU)
The single Euro PIU module is the interface between the Base Station site's DC 
power source and the Base Station chassis PSUs and external AU ODUs, which 
receive power via the AU-IDUs. 
The PIU filters and stabilizes the Base Station input power and protects the 
system from power problems such as over voltage, surge pulses, reverse polarity 
connection and short circuits. It also filters high frequency interference (radiated 
emissions) and low frequency interference (conducted emissions) to the external 
power source. Each Base Station chassis contains two slots for an optional 1+1 
PIU redundancy. One PIU is sufficient to support a fully populated chassis. Two 
PIU modules provide redundant power feeding (two input sources) while avoiding 
current flow between the two input sources.
Table 1-1: Number of AU-IDUs, AU-ODUs and Power Feeders Required for Various Configurations 
with regular PIU(s)
Diversity 
Mode
Number of Sectors 
(AU-IDUs)
Number of 
ODUs
Number of 
Power Feeders
Second Order 
Diversity
3
6
-
4
8
-
6
12
1
Fourth Order 
Diversity
3
12
1
4
16
2
6
24
4
Table 1-2: Number of AU-IDUs, AU-ODUs and Power Feeders Required for Various Configurations 
with High-Power PIU(s)
Diversity 
Mode
Number of Sectors 
(AU-IDUs)
Number of 
ODUs
Number of 
Power Feeders
Second Order 
Diversity
3
6
-
4
8
-
6
12
-
Fourth Order 
Diversity
3
12
-
4
16
-
6
24
1