COMMUNITY CELLULAR NETWORKSKURTIS HEIMERL

SHADDI HASAN

COLLABORATORS

ME

SO WHAT IS IT THAT WE DO HERE?

ESSENTIALLY…We build cell phone towers and technologies for places that do not currently have them. Many reasons for this…

• Economics

• Policy

• Etc…

WHAT’S A CELL TOWER?You may expect this…

WHAT’S A CELL TOWER?But it’s actually this.

Base Transceiver Station getting smaller and cheaper

• 500k USD -> 10k USD

• 1 kW -> 70W

So on…

Suddenly in the range of individuals/entrepreneurs.

MOORE’S LAW IN ACTION

OUR WORK EXPLORES…

1. Technology

• Technological changes required to realize this vision of a distributed cellular network

• Technological changes required to bring these networks to the billions currently without cellular coverage

• Systems for supporting the customization of small scale cellular networks

OUR WORK EXPLORES…

1. Technology

2. Policy

• Policy and regulatory changes required to support these networks and allow them to interoperate and coexist

OUR WORK EXPLORES…

1. Technology

2. Policy

3. Social

• Sustainable deployment of these technologies in real world populations

Virtual Coverage [1]: We added a hardware switch to control the power amplifier.

This allows us to save power at night and further reduce power draw of the BTS.

[1] Expanding Rural Cellular Networks with Virtual Coverage NSDI ‘13

TECH – POWER SAVINGS

Village Base Station [2] – Set of scripts to enable extreme customization of network to specific communities. Includes:

• SMS

• Voice

• Naming

• Routing

• Etc…

[2] Local, Sustainable, Small-Scale Cellular Networks ICTD’13

TECH – PROGRAMMABILITY

Nomadic GSM [3]: Technique for allowing unlicensed system to utilize fallow spectrum in GSM bands for cellular operation

Core techniques:

• Phones scan

• Constant migration

• Self-handover

[3] GSM Whitespaces: An Opportunity for Rural Cellular Service DySPAN ‘14

POLICY – GSM WHITESPACES

Burning Man 2011, 2012…

We run a full telco for the BM community providing outbound connectivity on the Playa

SOCIAL - DEPLOYMENTS

Papua, Indonesia 2012

Ongoing deployment in collaboration with local school [2]. Full market economy, generating revenue for local participants and providing basic communications to an area without coverage.

[2] Local, Sustainable, Small-Scale Cellular Networks ICTD’13

SOCIAL - DEPLOYMENTS

Papua, Indonesia 2012

Also deployed virtual coverage in the same community [4].

[4] An Experiment in Reducing Cellular Base Station Power Draw With Virtual Coverage DEV 4

SOCIAL - DEPLOYMENTS

SOCIAL - SUSTAINABILITY

SOCIAL - SUSTAINABILITY

Growth Rate Profit

0 users/month $368.31

2 users/month $400.71

5 users/month $433.11

10 users/month $478.47

FIN

SHADDI@CS.BERKELEY.EDU

HTTP://CS.BERKELEY.EDU/~SHADDI