NOTE: All information here is collected by us, we have no contact or affiliation with Ericsson. We have no idea how accurate our information-gathering has been.

Ericsson Mini-Link

Ericsson Mini-Link is a series of commercially very successful microwave links.

They are used world-wide for back-hauling GSM BTS and UMTS Node-B, i.e. for the A-bis and IuB-links.

Every microwave link is a point-to-point link.

Each side of the link has an IDU (In Door Unit) and ODU (Out Door Unit).

IDU (MMU)

The IDU is responsible for transmitting and receiving at the respective microwave frequency (normally 7...38GHz).

In the Mini-Link system they are most commonly they are called MMU.

There are different types of MMUs, representing the different link speeds of the microwave link, e.g.

  • MMU 34+2 (1 E3 link at 34 Mbps plus 1 E1 link for mgmt)
  • MMU 4x2 (4 E1 links at each 2 Mbps)

The MMU has connections for the data links (E1, E3, STM-1, etc.) as well as a coaxial wire connecting it with the ODU.

You can see photographs of the interior of a MMU in the following album:  http://laforge.gnumonks.org/photoalbum/devices/ericsson_minilink/mmu_34_2/index.html

SMU

The SMU is a unit that aggregates SDH links, e.g. the SAU 16x2 aggregates 16 E1 links into one E3

 http://laforge.gnumonks.org/photoalbum/devices/ericsson_minilink/smu_16_2/index.html

SAU

The SAU can control various site-local digital input and outputs throug the management link.

 http://laforge.gnumonks.org/photoalbum/devices/ericsson_minilink/sau_exp1/index.html

ODU (RAU)

The ODU is contains the actual modem that modulates the E1, E3 or STM-1 link onto the IF (Intermediate Frequency) which is put on the coaxial link towards the ODU.

Conversely, on a different IF, there is the down-link from the ODU towards the demodulator/decoder in the IDU.

In the Mini-Link system, the ODU is commonly called RAU (Radio Access Unit).

Hardware Information

IF-Link between IDU and ODU

There are three intermediate frequencies (IFs) that are being used:

  • Uplink IF at 350 MHz
  • Downlink IF at 140 MHz
  • Control IF at low frequency

Mini-Link Equipment that we have

RAU

7 GHz

QtyTypeTx (MHz)Owner
1RAU1 N 7/117426-7484Jolly

15 GHz

QtyTypeTx (MHz)Owner
1RAU 15/1314709.25-14823LaForge? (D)
1RAU 15/1615024.25-15138LaForge? (D)

18 GHz

QtyTypeTx (MHz)Owner
1RAU1 18/1117706.5-18009.5LaForge?
1RAU1 18/1518716.5-19019.5LaForge?

23 GHz

QtyTypeTxOwner
1RAU 23/5622002.75-22513.75Jolly
1RAU2 L 23/7622002.75-22288Jolly
1RAU2 N 23/7622002.75-22288Jolly
1RAU2 M 23/7722288-22590.75LaForge?
1RAU2 M 23/7923296-23598.75LaForge?

26 GHz

QtyTypeTx (MHz)Owner
1RAU 26/2424995.25-25445LaForge?
1RAU 26/2926003.25-26453LaForge?

38 GHz

QtyTypeTx (MHz)Owner
1RAU 38/1237338-37619.75Jolly
1RAU 38/1638598-38879.75Jolly

MMU

QtyTypeOwner
3MMU 34+2LaForge?
6MMU 34+2Jolly
3MMU 155/16Jolly
3MMU 155/128Jolly
2MMU 4+2/8LaForge? (D)

SMU

QtyTypeOwner
2SMU 16x2LaForge?

SAU

QtyTypeOwner
1SAU 1 ExpLaForge?

Other (Not Ericsson)

QtyTypeOwner
2RAD 34M/E1Jolly