Cityscape: Distributed, Persistent RF Monitoring With

CityScape: Distributed, Persistent RF Monitoring with

Commodity SDR Sensors

https://cityscape.cloudapp.net

Sumit Roy U. Washington, Seattle ()

This NSF funded and Microsoft-for-Azure supported[1] project has deployed a state-of-art spectrum monitoring infrastructure that demonstrates feasibility of persistent spectrum monitoring with I-Q data generation using commodity (low cost) sensor hardware (Software Defined Radios) along with a robust software control/management infrastructure (the web portal, link above) that

a)  allows for stations hosts/project PI to set knobs for data acquisition as desired (within sensor capability limits);

b)  stores the sensor data is stored in Microsoft Azure Public cloud, available for download by the community for post-processing freely.

Currently – there are 5 active (and 6th soon to be deployed) stations in metro Philadelphia, PA area (visible as green icons @ cityscape.cloudapp.net in the map GUI) + 2 test stations in Seattle (on U. Washington and Microsoft Redmond campus) from which raw I-Q and aggregate power spectrum density (p.s.d) data is being collected. See Fig. 1 for an architectural overview of the data acquisition and upload process and [1] for further information.

Fig 1: Cityscape Architecture

INVITATION TO NSC COMMUNITY FOR USE OF THIS RESOURCE

Prospective users are invited to send an email to with cc to Project PI (). We are available to discuss custom spectrum data acquisition to suit your needs in the 300 MHz- 6 GHz range.

FAQ

l  What is the address of the web portal?

A: http://cityscape.cloudapp.net/; navigate using buttons on the left pane.

l  Q: How can I process data files?

A: Sample parsers are available @

https://github.com/cityscapesc/specobs/tree/master/main/tools .

l  Q: Are the source codes of the project available?

A: Source codes are available under Apache License 2.0 @

https://github.com/cityscapesc/specobs/

l  Q: What is the RF performance & hardware specifications for stations?

A: The sensors are based on USRP N200 + UBX-40, refer to the datasheets and measurements from Ettus Research (www.ettus.com) .

l  Q: Are all sensors calibrated?

A: Yes, all officially deployed sensors in Philadelphia (and the Seattle test stations) are calibrated and the calibration information stored on each sensor’s host PC.

l  Q: Can CityScape collect I-Q data in a scan continuously?

A: A scan = multiple sequential snapshots. A full scan ~0.5s @ 25MS/s, the re-tune delay (~ few ms.) between each snapshot implies there is a small time gap between each snapshot. However, data is continuous if there is no scanning.

l  Q: What is the minimum averaging duration for the CityScape PSD estimates?

A: 10 seconds. Typical setting = 1 min. Alternatively, you can generate your own PSD estimates (with desired averaging durations) by downloading and processing raw I-Q data.

l  Q: Does the USRP front-end have an AGC?

A: No, the gain level must be manually chosen for now for any bands at each location.

Useful Links

[1] https://depts.washington.edu/funlab/projects/software-defined-wireless-networks/cityscape-project/

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[1] An Azure-for-Research award has underwritten costs for cloud storage and transactions for duration of this effort.