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).


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

You can see photographs of the interior of a MMU in the following album:


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


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


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


7 GHz

Qty Type Tx (MHz) Owner
1 RAU1 N 7/11 7426-7484 Jolly

15 GHz

Qty Type Tx (MHz) Owner
1 RAU 15/13 14709.25-14823 LaForge (D)
1 RAU 15/16 15024.25-15138 LaForge (D)

18 GHz

Qty Type Tx (MHz) Owner
1 RAU1 18/11 17706.5-18009.5 LaForge
1 RAU1 18/15 18716.5-19019.5 LaForge

23 GHz

Qty Type Tx Owner
1 RAU 23/56 22002.75-22513.75 Jolly
1 RAU2 L 23/76 22002.75-22288 Jolly
1 RAU2 N 23/76 22002.75-22288 Jolly
1 RAU2 M 23/77 22288-22590.75 LaForge
1 RAU2 M 23/79 23296-23598.75 LaForge

26 GHz

Qty Type Tx (MHz) Owner
1 RAU 26/24 24995.25-25445 LaForge
1 RAU 26/29 26003.25-26453 LaForge

38 GHz

Qty Type Tx (MHz) Owner
1 RAU 38/12 37338-37619.75 Jolly
1 RAU 38/16 38598-38879.75 Jolly


Qty Type Owner
3 MMU 34+2 LaForge
6 MMU 34+2 Jolly
3 MMU 155/16 Jolly
3 MMU 155/128 Jolly
2 MMU 4+2/8 LaForge (D)


Qty Type Owner
2 SMU 16x2 LaForge


Qty Type Owner
1 SAU 1 Exp LaForge

Other (Not Ericsson)

Qty Type Owner
2 RAD 34M/E1 Jolly

Updated by jolly almost 8 years ago ยท 9 revisions

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