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Ericsson RBS6000 Series
=======================
:author: Harald Welte <laforge@gnumonks.org>
:copyright: 2018 by Harald Welte (License: CC-BY-SA)
:backend: slidy
:max-width: 45em
== Ericsson RBS 6000 Series
* very popular series of Radio Base Stations (RBS) during last decade
* supports _many_ different configurations built from various modules
** *Digital Units* (DU)
** *Radio Units* (DU)
** miscellaneous bits like shelves / racks, fans, fuses, OVP, cables, PSU, ...
* supports both
** classic BTS cabinets with radio
** remote (tower mounted) radio heads
== RBS 6000 Series Overview
image::rbs6k-intro.png[width="100%"]
== Think of it as "Lego"
image::rbs6k-lego.png[width="100%"]
== Example: RBS6201 Rack
image::rbs6201-rack.png[width="75%"]
== Example: RBS6201 Shelf
Example shelf with 6x radio unit and 1x WCDMA digital unit
image::rbs6201-shelf.png[]
== GSM: DUG 10 + RUG
* first generation GSM modules for RBS6000
* closely resembles RBS2000 architecture
** *DUG 10* like RBS2000 IXU/DXU
** *RUG* like RBS2000 RRU: TRX
* interconnection between DUG 10 + RUG is still TDM, not baseband samples!
== Digital Unit GSM *DUG 10*
* up to 12 TRX, grouped in 1..6 logical BTS
* matches most closely IXU or DXU of previous RBS2xxx series
* no baseband processing inside, just protocol logic (LAPDm + RSL + OM2000)
* 6x HSIO connector for interface towards *RUG*
* 4x E1/T1 ports exposed on RJ45 connectors
== Radio Unit GSM *DUG*
* GSM only
* 2 TRX in hardware
** any of them can be GSM, WCDMA or LTE
* 48W per TRX un-combined
* 22W per TRX combined (internal hybrid combiner)
image::dug.png[]
== GSM: DUG 20 + RUS
* second generation GSM modules for RBS6000
* more closely resembles the UMTS + LTE modules
* all baseband processing in *DUG 20*
** digital baseband I/Q samples between *DUG 20* and *RUS*
* interconnection uses CPRI (Common Public Radio Interface)
* connectors typically SFP format.
** can be used with SFP optics + fiber (many km long)
** can be used with direct copper SFP interconnect cables (few m)
== Digital Unit GSM *DUG 20*
* up to 12 TRX, gruoped in 1..6 logical BTS
* includes baseband processing, unlike DUG 10
* 6 SFP slots with CPRI towards Radio Units (*RUS*)
* 4x E1/T1/J1 ports exposed on two RJ45 connectors
== Radio Unit Mulit-Standard *RUS 01*
* GSM WCDMA and LTE
* 4 carriers over 20 MHz IBW
** any of them can be GSM, WCDMA or LTE
* up to 1x 80W (one multi-channel PA)
** 20W without special license key
** up to 80W with license keys
image::rus.png[]
* RUS 02 has 40 MHz IBW
** up to 8 GSM carriers
** up to 4 WCDMA or LTE carriers
== UMTS: DUW + RUS
* *DUW* is Digital Unit WCDMA
* is used with RUS or RRUS (like DUG 20)
* offers Iub interface to RNC
* no FOSS RNC, so not very interesting :(
== LTE: DUL + RUS
* *DUL* is Digital Unit LTE
== Combined UMTS + GSM setup (classic approach)
image::1ru_per_sector_rbb12_1a.png[width="100%"]
* works the same way with DUL + DUG for LTE + GSM
== Combined UMTS + GSM setup (classic approach)
image::2ru_per_sector_rbb22_2b.png[width="100%"]
* works the same way with DUL + DUG for LTE + GSM
== GSM/UMTS/LTE in one: DUS 31 / 41
* *DUS* are _multi-standard DU_ (GSM/UMTS/LTE)
* DUS 31 capacity up to 24 GSM TRX
** or up to 12 GSM TRX combined with LTE
* DUS 41 capacity up to 48 GSM TRX
** or up to 12 GSM TRX combined with LTE
* Back-haul is Ethernet only, no E1/T1/J1 anymore
** it is presumed that it's like an internal software-only SIU-02
image::dus4101.png[]
== Ericsson + Osmocom
We do have some history of RBS2000 support
* OsmoNITB has OM2000 implementation proven with RBS2000
* OsmoBSC inherits that, but breaks voice (no E1 in `osmo-mgw` yet)
* OsmoBSC has `pcu_sock` interface for BSC-colocated PCU
* Adding E1/TDM user plane support to osmo-mgw would enable using Ericsson RBS again
* All that's missing for low-cost macro BTS with Osmocm is an inexpensive E1 interface
** see separate talk
== EOF
End of File
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