ZINWAVE 2700
DISTRIBUTED ANTENNA SYSTEM
-
INSTALLATION AND TECHNICAL MANUAL
ZINWAVE 2700 DAS - INSTALLATION AND TECHNICAL MANUAL
Page 22
Table 4-2 indicates that for an area of 2500 m
2
then the maximum number of TOs is 12 No. for an elongated space and 9
492
No. for a “square” space. By reference to building drawings and appropriately careful placement of TOs, the actual
493
number of TOs will be less than that specified in Table 4-2.
494
495
It should be noted that the number of TOs does not mandate the number of ZinWave 2760 or 2776 Antenna Units or the
496
usage of those Antenna Units (see 4.8). However, the number of TOs does define the number of optical fibres to be
497
provided from the FD/HC, and where a direct correspondence is applied, the number of optical fibres required in the
498
backbone cabling subsystem which services the FD/HC.
499
500
501
4.3
Selection of optical fibre cabling media
502
4.3.1
ZinWave 2700 DAS integration within generic/structured cabling infrastructures
503
4.3.1.1
General
504
The number of TOs to be served by each FD/HC defines the number of optical fibres required in the building backbone
505
cabling at each FD/HC.
506
507
As building backbone cabling already exists it has to be determined if the existing optical fibre cables serving the FD/HCs
508
have adequate numbers of unused (or reassignable) optical fibres. If not then additional backbone cables are required.
509
510
Clause 4.3.1.2 discusses the re-use of existing singlemode optical fibre backbone cabling.
511
512
Clause 4.3.1.3 discusses the re-use of existing multimode optical fibre backbone cabling.
513
514
Clause 4.3.1.4 discusses installation of additional backbone cabling.
515
516
The selection of the optical fibre media to be used and how they are to be connected should also take into account the
517
considerations of channel length and channel insertion loss outlined in clause 4.3.3.
518
519
4.3.1.2
Re-use of existing singlemode backbone cabling
520
It is not uncommon for premises to have backbone cabling to comprise both multimode and singlemode optical fibres
521
either as separate or composite cables. If there are insufficient multimode optical fibres available, it may be that the
522
singlemode optical fibres are unused. In such cases, as the ZinWave 2700 DAS is “fibre-agnostic”, it reasonable to use
523
the singlemode backbone cabling and to implement the generic wireless application overlay cabling in singlemode
524
cabling also. This has the benefit that no ZinWave proprietary pigtails, launch cords and patchcords are required
525
anywhere within the ZinWave channel.
526
527
If there are adequate numbers of unused (or reassignable) singlemode optical fibres in the building backbone cabling
528
then their use for the ZinWave 2700 DAS will require either:
529
•
a crossconnection using an industry-standard singlemode “patch cord” between the existing backbone panel and the
530
ZinWave Termination Panel in the FD/HC as shown in Figure 4-5;
531
or, where there are enough optical fibres in an existing singlemode optical fibre backbone cable to allow the allocation of
532
a complete cable to the ZinWave 2700 DAS;
533
•
the replacement of the backbone cabling panel and the ZinWave Termination Panel with a ZinWave Splice panel as
534
shown in Figure 4-6.
535
536
The latter enables a lower channel insertion loss (see 4.3.3) and more secure distribution of the services provided over
537
the ZinWave 2700 DAS. It is also the preferred approach if additional backbone cabling is to be installed (see 4.3.1.4).
538
539
WARNING:
Customers may be unwilling to allow partial re-work to be undertaken on a backbone cabling panel if other services are
540
already operating though the optical fibre contained within it.
541
542
WARNING:
Installers may be unwilling to accept responsibility for the modifications made to existing cable plant. The opening of
543
backbone panels may:
544
a)
be difficult due to poor cable dressing practice in the cabinets that puts both the re-work and other cabling at risk;
545
b)
determine that inadequate lengths of optical fibre exist in the panels to allow fusion splicing of the ZinWave hi-conn
546
pigtails;
547
c)
determine that the management practices for the optical fibre within the panels puts other optical fibres at risk.
548
