Exhibit A

0048-EX-PL-2007 Text Documents

ViaSat, Inc.

2007-02-12ELS_79606

                    EXHIBIT A




              EXPERIMENTAL PROGRAM




DC\959724.1


Request for STA

ViaSat, Inc. ("ViaSat") files this request for a new experimental license to authorize the
experimental VSAT facility that was previously authorized under call sign WD2XAQ1.
Due to an administrative oversight, ViaSat inadvertently failed to renew this
authorization and thus, it expired on January 1, 2007. ViaSat has ceased operations of
this facility. Simultaneously with this application, ViaSat is seeking special temporary
authority to allow testing on this facility while this application for long-term authority
remains pending.

Equipment Description

The first generation ArcLight VSAT product was designed to utilize a standard DVB-S
forward channel from the hub earth station to the remote VSAT earth stations. The
DVB-S forward channel could be operated at a variety of data rates up to 54 MHz of
occupied bandwidth.

The second (and current) generation of ArcLight product uses a direct sequence spread
spectrum forward channel. The forward link encapsulates Internet Protocol (IP) data and
modulates it using phase shift keying and a spreading sequence to occupy up to 36 MHz
of bandwidth. Optionally, low chipping rates may be used to enable half-transponder
operation. The current range of supported data rates for the forward link is 512 kbit/s to
10 Mbit/s.

As part of this experimental program, ViaSat also plans to develop a new version of the
forward channel modulator that adds the capability to transmit fully compliant DVB-S2
signals in either spread or unspread mode.

The return channel from the remote VSAT earth stations will continue to utilize the same
code reuse multiple access (CRMA) direct sequence spread spectrum technology as the
current generation product, but additional data rates and capabilities will be tested. The
VSATs will be able to access the return channel using a number of different data rates –
32, 64, 128, 256, 512, and even 1024 kbit/s. The chip rate may be varied to allow the
data to be spread to lower the power spectral density to enable operation from very small
aperture mobile terminals. The return channel employs GMSK constant envelope phase
shift keyed modulation and data is Forward Error Correction (FEC) encoded using a rate
1/3 Turbo-like FEC.

The return channel multiple access architecture is random access where IP data is
encapsulated into ATM cells. A unique preamble is utilized for each permutation of data
rate and packet size defined in the system. In this CRMA scheme, the same spreading
code is used for each transmission by VSATs operating at a given return channel data
rate. The correlators at the hub station then separate each burst by time of arrival.

1
    See File No. 0251-EX-PL-2002, modified by File No. 0030-EX-ML-2003, renewed by
          Filed No. 0026-EX-RR-2005.


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Normally, the forward and reverse channels would have to occupy different frequencies
on the satellite. At typical forward channel data rates and high return channel chip rates,
a separate transponder would be required for each direction. However, ViaSat has
invented a self-interference cancellation technique where by the forward and return
channels may operate at the same frequency at the same time within the satellite
transponder. At the hub, the canceller keeps a copy of the transmitted forward link signal
in memory and matches the time, phase, and amplitude of the transmitted forward link
carrier as it is received at the hub and effectively cancels it by 25 dB or more. This then
allows the receiver at the hub to successfully demodulate the inbound signals from the
remote VSATs.

Because the composite power spectral density of the return link carriers is very low with
respect to the forward link, and because the G/T of the VSAT antennas is small, there is
little interference from return link carriers to the forward link signal being received by the
remote VSATS.

As part of the experimental program, a number of sub-meter VSAT antennas will be
evaluated for use in a mobile environment. While these VSAT antennas do not meet the
FCC part 25.209 antenna performance standards, the aggregate off-axis input power
density of all of the antennas under test will be controlled such that the FCC part 25.134
antenna input power density limit of –14 dBW/4 kHz will be not be exceeded. That is,
the antenna input power density for each part 25.209 compliant antenna will be reduced
such that it does not exceed –14 dBW/4 kHz – 10 * log(N) where N is the number of
simultaneously transmitting antennas.

The antenna input power density for each part 25.209 non-compliant antenna will be
similarly reduced such that its input power density does not exceed –14 dBW/4 kHz – 10
* log(N) minus the additional number of dB that its antenna pattern falls short of meeting
part 25.209 at the adjacent satellites.

As an example, operating at a chipping rate of 28.8 Mchip/s, a typical spreading rate to
be used, the typical maximum antenna input power density at which any antenna could
operate is 10 * log(2 W) – 10 * log(14.4 MHz / 4 kHz) = -35 dBW/ 4 kHz and given the
small number of terminals to be employed in the experimental program, interference into
the adjacent satellites will not be a problem.




DC\959724.1


Experimental Program

The proposed program of experimentation is designed to allow ViaSat to continue to test
and verify the performance of its ArcLight VSAT product and make product
enhancements as required to meet market needs.

The hub antenna will typically be located and operational at ViaSat’s Carlsbad, CA
facility, but additional test hubs will be located in the areas identified in the application
form, and other test hubs may be put into operation within CONUS as required to support
limited demos and tests. The mobile terminals will be located within CONUS.

ViaSat requests ALSAT authority; however, the experimental facility will communicate
primarily with AMC-6 at 72º W.L., with NSS-7 at 22º W.L. being used for automated
satellite handover testing.

The test program consists of, but is not necessarily limited to, the following:

    •   Verification of hub and remote terminal modem and RF performance
    •   Verification of hub and remote power spectral density masks
    •   Verification of mobile antenna auto-tracking performance
    •   Verification of terminal throughput under various load conditions
    •   Verification of system capacity under various load conditions
    •   Verification of system network management functions such as uplink power
        control, network aggregate off-axis EIRP density management, network load
        congestion control, remote subscriber terminal configuration and maintenance,
        and commanded transmit inhibit of remote terminals
    •   Verification of subscriber installation, configuration, antenna pointing aid tools,
        and transmit inhibit on loss of forward link reception
    •   General system performance benchmarking and modeling




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Contribution To The State Of The Art

The ArcLight product is currently in operation and providing service to business jet users
via ARINC’s SKYLinkSM service. Testing under ViaSat’s experimental license
WD2XAQ allowed ViaSat to develop the ArcLight product to the point where it was
commercially viable for that application. Government and commercial customers have
continued to push for new mobile uses, and ViaSat fully expects to be able to make the
evolutionary changes required to support these exciting new applications. Once
successfully tested and ready for deployment, the ArcLight product offers several key
advantages over existing VSAT products.

    •   By using direct sequence spread spectrum and GMSK modulation on the return
        links, the terminal size and cost can be reduced without increasing the risk of
        causing harmful interference to other satellite systems.
    •   The high spreading rates supported by the system can reduce uplink power
        spectral density significantly and thereby enable mobile operation of sub meter
        class antennas without risk of causing harmful interference to adjacent satellite
        operators even if precise antenna is not maintained.
    •   Antenna pointing aids and uplink power control are built into the product to help
        insure that the subscriber terminals are correctly pointed and that they operate
        with only the minimum necessary power. Failsafe mechanisms are built in to the
        subscriber terminal to insure that is ceases transmission when the equipment
        malfunctions or when the terminal’s antenna is mispointed.
    •   The code reuse multiple access (CRMA) direct sequence spread spectrum return
        links share the low delay features of conventional TDM/TDMA random access
        VSATs in that data is sent as soon as it is received, but is implemented in such a
        way as to allow the system operator and the user added flexibility in the number
        of data rates that can be supported without increasing the cost and complexity of
        the subscriber terminal.
    •   CRMA also reduces the complexity and cost of the hub station because with all
        transmission sharing a common spreading code, only a single correlator is needed
        for each chipping rate.
    •   The integrated self-interference cancellation at the hub station using ViaSat’s
        patented PCMA technology allows for a tremendous reduction in the satellite
        bandwidth required to operate the network. Previously VSAT to hub links at the
        high chipping rates the ArcLight system can employ would have resulted in
        seriously bandwidth limited operation on the satellite transponder – much of the
        transponder power would have gone unused. Using the PCMA hub canceller, the
        high power forward link to the VSATs can now share the same bandwidth with
        the low power VSAT return links.




DC\959724.1



Document Created: 2007-02-12 10:42:26
Document Modified: 2007-02-12 10:42:26

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