The information contained in this feature description document is proprietary and confidential It may not be reproduced or distributed without the express written permission of Nextivity Inc. 

  

Cel‐Fi Feature Description: Cel‐Fi System Overview    

Overview The Cel-Fi system is a new class of coverage solution which has been proven to dramatically improve indoor voice coverage and wireless data rates. It does so while being transparent to the network and without changing the interference characteristics of the network. Cel-Fi provides gain to mobile wireless signal and increases the footprint, or coverage, of the network. Detailed Description Cel-Fi consistently provides higher gain than competing indoor coverage systems, it and does not require the use of a fixed broadband connection. This is achieved through the two box approach:

The two boxes are the window unit (WU), which is placed at a location in the building which is within the coverage area of the network, and the coverage unit (CU), which is placed inside the building. The CU radiates the downlink frequencies and receives the uplink frequencies. The mobile wireless signal is transferred with high fidelity and extremely low latency between the two boxes on a 5 GHz unlicensed link using technology developed by Nextivity. The physical isolation (distance, path loss) between the two boxes allows for high system gain without introducing self-echo related instability. The WU contains four 90 degree high-gain directional antennas the best antenna is selected by the WU based on a combination of factors. The use of a directional antenna at the window unit (WU) allows for high antenna gain, which in turn leads to better sensitivity than a UE at the same location and therefore increase to the Node B coverage, which in turn is extended by providing a system gain to this signal. In other words the coverage improves for two reasons – the increased sensitivity of the WU (a few dB of improvement to the link budget) and the repeater system gain (up to 100 of dB of improvement to the link budget). This improved link budget gain and the improved antenna selectivity have the combined effect of increasing the RAN capacity of the wireless network.

The information contained in this feature description document is proprietary and confidential It may not be reproduced or distributed without the express written permission of Nextivity Inc. 

The Cel-Fi system frequency locks to specific UMTS carrier frequencies and is capable of reading network parameters such as PLMN-ID; system gain is maximized while not causing any adverse effects on the wireless network. The Cel-Fi system implements “Uplink Safe Mode”:

Cel-Fi uses the path loss from the Node B to set the uplink (UL) system gain such that repeater receiver noise is not received at a level that can de-sensitize the Node B.

Cel-Fi turns off the uplink completely where no mobile devices are active within the coverage area of the CU (also called ‘uplink gating’)

Finally, the Cel-Fi system is capable of detecting other local wireless devices using 5GHz channels (including other Cel-Fi units) and take action to avoid interference. The system is able to safely co-exist with other units and remain stable at all times allowing for a mass deployment of units and thus making Cel-Fi a truly scalable product line. A range of Cel-Fi products are available and planned which operate in different 3GPP bands and boost different numbers of carrier frequencies:

Product # Carrier Frequencies boosted 3GPP Bands supported Cel-Fi RS1 1 Bands I and IV Cel-Fi RS2 1, 2 or 3 Bands I, II, IV, V and VIII

Cel-Fi supports a number of unique features which differentiate it from other coverage solutions; the table below summarises the features, availability and supported hardware.

Feature Commercially

Introduced Supported on Cel-

Fi RS1 Supported on Cel-

Fi RS2 RS1 User Interface June 2009 YES NO RS2 User Interface March 2011 NO YES Antenna Selection June 2009 YES YES Carrier Selection for Single Carrier

June 2009 YES YES

Carrier Selection for Multi-Carrier

March 2011 NO YES

Automatic Gain Control and Network Safety

June 2009 YES YES

Cel-Fi Co-existence June 2009 YES YES Security and Factory Provisioning

June 2009 YES NO

Security and Factory Provisioning – RS2

March 2011 NO YES

The information contained in this feature description document is proprietary and confidential It may not be reproduced or distributed without the express written permission of Nextivity Inc. 

Location Lock November 2009

YES YES

Remote Disable November 2009

YES YES

Advanced Remote Disable

May 2010 YES YES