POWDER-RDZ: the POWDER Radio Dynamic Zone

POWDER-RDZ is a radio dynamic zone being created at the University of Utah's POWDER mobile and wireless network testbed. As a full-featured automated testbed for outdoor over-the-air wireless network research, POWDER natively provides some features of a zone management system (e.g. spectrum scheduling and monitoring, automatic RF kill switch on transmit violation, and more). However, it lacks more advanced zone management features: parallel same-band spectrum sharing, detailed network planning, occupancy analysis, risk analysis and automatic interference report and transmission violation mitigation.

The POWDER-RDZ portal can be accessed at https://rdz.powderwireless.net .

POWDER-RDZ was introduced in this paper at DySPAN '24:

POWDER-RDZ: Prototyping a Radio Dynamic Zone using the POWDER platform

David Johnson, Dustin Maas, Serhat Tadik, Alex Orange, Leigh Stoller, Kirk Webb, Basit Awan, Jacob Bills, Miguel Gomez, Aarushi Sarbhai, Greg Durgin), Sneha Kumar Kasera, Neal Patwari, David Schurig, and Jacobus (Kobus) Van der Merwe

IEEE International Symposium on Dynamic Spectrum Access Networks (IEEE DySPAN) 2024.

POWDER-OpenZMS Integration

POWDER and OpenZMS are separate software systems. POWDER-RDZ is a deployment of OpenZMS, and POWDER utilizes OpenZMS spectrum management services by integrating with the OpenZMS ZEAL northbound APIs. Using these APIs, POWDER does the following:

• Implements the Provider role: POWDER delegates some of its accessible outdoor spectrum to OpenZMS for management and monitoring
• Implements the Consumer role: when experiments request to use some of the delegated spectrum, POWDER requests a spectrum grant from OpenZMS according to the experiment requirements, and provides that grant to the experiment
• Implements the Monitor role: provides the output of POWDER over-the-air monitors (power spectral density data) and inline, coupled TX monitors

As part of implementing the Consumer and Monitor roles, POWDER populates the OpenZMS data model with all necessary information about its radios: location, antenna, capabilities, and more. This provides OpenZMS with the necessary radio metadata to perform on-demand, high-fidelity network planning to support spectrum sharing, as well as monitoring data to ensure safe sharing.

POWDER-RDZ: OpenZMS Zone Status

The following screenshot shows the zone-wide OpenZMS status page. The map shows the University of Utah campus area covered by POWDER's FCC Program Experimental License and Innovation Zone designations and many of the locations of POWDER radios as blue markers. The navbar to left of the map allows users to filter the map display by

• Spectrum: delegated bands provided to OpenZMS to manage
• Grants: active/revoked grants scheduled by OpenZMS
• Radios: transmitters, receivers, monitors

POWDER-RDZ: OpenZMS Zone Status

The OpenZMS status map shows live observation data from selected monitors. This is a power spectral density graph produced by the POWDER over-the-air monitor running on an NI X310 USRP software-defined radio on the honors rooftop, targeted to sweep lower c-band and CBRS.

POWDER-RDZ: POWDER mobile 5G experiment Setup

This screenshot shows a freshly-instantiated mobile 5G experiment on POWDER, using the srs-outdoor-ota POWDER profile. This profile creates a mobile 5G deployment from bare metal: it allocates one or more of POWDER's densely deployed SDRs with medium-power RF frontends, campus shuttles carrying POWDER SDRs and COTS UEs, configures srsRAN 5G base gNodeBs atop them, giving the user a real 5G network deployment.

POWDER-RDZ: POWDER mobile 5G experiment Using Spectrum

This profile and screenshot use the POWDER-RDZ capabilities. When the experiment was created, POWDER requested a grant of available, unoccupied lower c-band spectrum from OpenZMS, and OpenZMS returned a 20MHz grant around 3480MHz. POWDER provided that information to the experiment, and the 5G network was created using that spectrum.

In the screenshot below, you can see that the POWDER OTA monitor used by OpenZMS to select a range of unoccupied spectrum is now showing occupancy at 3480MHz, as the mobile COTS UEs connect to the gNodeB and run throughput tests.