7
V. The frequency bands available cover the standard bands 6 to 42 GHz. Microwave signals do not
penetrate buildings, vegetation or terrain nor bend around obstacles. Therefore the antenna has to be
placed on top of a tall building or on a tall tower or mast in order to provide free line-of-sight connection to
the opposite end.
IPASOLINK 400
This guide is based on the middle-sized member of the family, the iPasolink 400. It may contain up to four
(4) modems. Each modem can provide Ethernet L2 capacity 10 to 400 Mbit/s or PDH/SDH capacity up to
152 x E1 or 2 x STM-1 or various combinations. The actual capacity depends on the available channel width
and available signal to noise/interference ratio and the fade margin required to fulfil the availability targets.
In the most basic configuration only one of the four slots contains a modem. The main card has always
FE/GbE and E1 interfaces. The other slots may contain additional GbE, SDH or E1 interfaces or modems. In
addition, TDM over packet (PWE), Synchronous Ethernet etc. options are available.
The highest capacities (400 Mbit/s) require access to a frequency band with 55 to 60 MHz channel spacing,
typically such channels are available in the upper 6 GHz, 18 GHz, 32 GHz or 38 GHz bands. On such bands
where the maximum spacing is only 27.5 or 28 MHz, the maximum capacity per modem is limited to about
200 Mbit/s. If necessary, two modems can share the same channel by using orthogonal polarizations and
XPIC (cross-polarization interference canceller). In such a setup the maximum combined capacity is about
400 Mbit/s (27.5 or 28 MHz channels) or about 800 Mbit/s (55 or 56 MHz channels).
The element management connection is based on Ethernet/IP transmission. All elements should be
connected to an EMS (PNMSj or MS5000). Within each iPasolink cluster the management traffic is carried
internally and separated from the customer traffic. A dedicated gateway connection (NMS port) to the
management data communication network (DCN) is typically used at the “root” element of the cluster.
Another solution is to use a traffic interface at the root element (in-band connection to root element).
Figure 1. iPasolink 400 indoor unit (IDU).