SAS - Spectrum Shared Access

Field trials of Citizens Broadband Radio Service (CBRS) / Spectrum Access System (SAS)

SAS work in CORE++ focus on trialling the latest US spectrum sharing concept for mobile broadband.

CORE++ project works on the US three-tier Citizens Broadband Radio Service (CBRS) model for 3.5 GHz band that introduces more dynamic sharing layer than the LSA model.

Work implements a SAS trial environment based on the Federal Communications Commission (FCC’s) definitions and Wireless Innovation Forum (WInnF) Spectrum Sharing Committee’s recommendations. Especially we have implemented the SAS-CBSD user interface.

CORE++ SAS/CBRS Trials give a unique opportunity to see live how a commercial LTE network adapts to the SAS frequency allocation.

The first SAS trial was presented in Globecom-2015 in San Diego, United States from 6th-10th December 2015

In the first demo, we have agreed with the project consortium to demonstrate the most basic characteristics of citizen broadband radio service (CBRS). It is the most straightforward extension of current LSA trial setup towards the CBRS/SAS concept.

The first trial consisted commercial LTE network components (base stations, user equipment, network management system, and core network) available at Ylivieska live LTE test network and Informing Incumbent.

In 2016 the CORE++ project developed the spectrum sharing specific components on top of the LTE system including Domain Proxy and algorithms for Spectrum Access System (SAS) to enable improved frequency allocation for the CBSDs. In the work both the standalone and operator driven CBSDs are considered. We also added sensoring system (ESC) and generation of Naval radar signals for the demonstrator purposes.

SmartCom 2016, Oulu, May 16-17 and European Wireless Conference (EW16), Oulu, May 18-20.

Live CBRS/SAS demos were presented, received The Best Demo Award of EW16

Demonstration at Crowncom 2016, France.

CBRS/SAS demo at CrownCom 2016, Grenoble, May 30-June 1, 2016

The demonstrator showed a provisioning of stand-alone CBSD and two CBSDs via MNO's Domain Proxy component. A naval radar was detected via sensoring system and CBSDs were managed by SAS to avoid the radar occupied bands. Here is Crowncom SAS demo proposal paper

CORE++ project had a live demo of CBRS/SAS trial at 5G demo day at Nokia premises in Oulu Finland during 8-9 September 2016.

This public event brought together companies and research from Finland and Norway and
The King and Queen of Norway visited there on 9 of September!

CORE++ demos at WInnComm-Europe 2016 in Paris 11-12 October 2016

CORE++ project presented two demos in WInnComm-Europe 2016 conference in Paris on 11-12 October 2016: “Rapidly Deployable Network Concept with Licensed Shared Access System“ and “Field Trial of Citizens Broadband Radio Service (CBRS) / Spectrum Access System (SAS)“.

The CBRS/SAS demonstrator is documented in the WinnComm-Europe 2016 demonstration paper. We provided updated measurements using the WinnComm-Europe demonstrator.

Video from trial presents CORE++ SAS with sensing capability, commercial base statations (CBSD-1 and 2) on live LTE network controlled by a Domain Proxy and OAM, one commercial base station (CBSD-3) as stand-alone LTE 3.5GHz small cell.

In the video, SAS manages four channels each 10MHz, three channels are for Priority Access users and one for General Authorized Access users. The base station CBSD-1 is PA user and the rest are GAA users. In the video the license owner (Naval radar) appears and is over PAL 1 and 2 channels. The SAS and Domain Proxy manages the CBSD-1 and CBSD-2 based on SAS to CBSD specification from

The main team for SAS / CBRS work is the following

  • CWC : Design and planning of SAS trials, participating WInnForum.
  • VTT : Design and implementing the SAS trials and interfacing other systems such as stand-alone LTE, database, visualisation and sensor system.
  • Centria & Nokia : Live LTE test network for SAS, Domain Proxy with operator-driven CBSDs
  • Bittium : Stand-alone LTE tools (Lite-EPC)
  • TUAS : Informing Incumbent, LSA/SAS Incumbent Repository & tools, sensoring system and radar signal generation.

Architecture of the CORE++ SAS field trial environment

Contact us:

VTT Technical Research Centre of Finland
Senior Scientist, Pekka Aho,
tel. +358 40 849 9525