Exhibit B Proposed Operations

0544-EX-ST-2007 Text Documents

DIRECTV Enterprises, LLC

2007-10-31ELS_85638

EXHIBIT B

PROPOSED OPERATIONS

DIRECTV proposes to operate the 17/24 GHz BSS payload on DIRECTV 11 at

the 101.6° W.L. ± 0.3° orbital location to conduct proof of concept video transmissions in

this newly available BSS band to determine the feasibility of the video link. Among

other things, DIRECTV also anticipates that the data it is able to collect from these

operations will provide valuable insights for the Commission’s pending rulemaking on

certain technical and sharing issues for the 17/24 GHz BSS service.1 For example,

DIRECTV operates DBS satellites at the nominal 101° W.L. orbital location that use the

same spectrum for uplink transmissions that the experimental payload on DIRECTV 11

uses for downlink transmissions. DIRECTV intends to assess the space path interference

caused by 17/24 GHz BSS downlink transmissions on reception of uplink transmissions

by nearby DBS satellites at varying levels of separation (i.e., by moving up to 0.3° from

101.6° W.L., both toward and away from 101° W.L.). It also hopes to evaluate the

ground path interference caused by DBS uplink earth station transmissions on reception

of the 17/24 GHz BSS downlink transmissions in areas near the DBS uplink earth station

site.

DIRECTV 11 is currently scheduled for launch in mid-January 2008.

Accordingly, DIRECTV requests that the STA begin effective March 1, 2008 and run for

up to one hundred twenty (120) days of operations by DIRECTV 11 at 101.6° W.L. ±

0.3° and by its earth station located in Moxee, WA.

1
See Establishment of Policies and Service Rules for the Broadcasting Satellite Service at the
17.3-17.7 GHz Frequency Band and at the 17.7-17.8 GHz Frequency Band Internationally,
and at the 24.75-25.25 GHz Frequency Band for Fixed Satellite Services Providing Feeder
Links to the Broadcasting-Satellite Service and for the Broadcasting Satellite Service
Operating Bi-directionally in the 17.3-17.7 GHz Frequency Band, 22 FCC Rcd. 8842 (2007).

B-1

Orbital Debris Mitigation

Pursuant to Section 5.63(e) of the Commission’s rules, DIRECTV submits the

following description of the design and operational strategies it will use to mitigate

orbital debris.

Spacecraft Hardware Design

DIRECTV has assessed and limited the amount of debris released in a planned

manner during normal operations. DIRECTV 11 will not be a source of debris during

launch, drift, or operating mode, as DIRECTV does not intend to release debris during

the planned course of operations of the satellite.

DIRECTV has also considered the possibility of DIRECTV 11 becoming a source

of debris by collisions with small debris or meteoroids that could cause loss of control of

the spacecraft and prevent post-mission disposal. As such, DIRECTV has taken steps to

address this possibility by incorporating redundancy, shielding, separation of

components, and other physical characteristics into the satellite’s design. For example,

omni-directional antennas will be mounted on opposite sides of the spacecraft, and either

will be sufficient to support orbit raising. The command receivers and decoders,

telemetry encoders and transmitters, and the bus control electronics are fully redundant,

physically separated, and located within a shielded area to minimize the probability of the

spacecraft becoming a source of debris due to a collision.

Minimizing Accidental Explosions

DIRECTV has implemented an overall spacecraft design that limits the

probability of accidental explosion. The key areas reviewed for this purpose include

leakage of propellant and mixing of fuel and oxidizer as well as NiH pressure vessels.

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The basic propulsion design (including component and functional redundancy, and the

placement of fuel tanks inside a central cylinder which provides a high level of

shielding), propulsion subsystem component construction, preflight verification through

both proof testing and analysis, and quality standards have been designed to ensure a very

low risk of propellant leakage and fuel and oxidizer mixing that can result in subsequent

explosions. During the mission, batteries and various critical areas of the propulsion

subsystem will be continually monitored (for both pressure and temperature) to preclude

conditions that could result in the remote possibility of explosion and subsequent

generation of debris.

After DIRECTV 11 reaches its final disposal orbit, all on-board sources of stored

energy will be depleted, all fuel line valves will be left “open,” any pressurized system

will be vented, and all batteries will be left in a permanent discharge state. The solar

cells will be slewed away from the sun to minimize power generation.

Through this process, DIRECTV will assess and limit the possibility of accidental

explosions during mission operations and assure that all stored energy at the end of the

satellite’s operation will be removed.

Safe Flight Profiles

DIRECTV has assessed and limited the probability of DIRECTV 11 becoming a

source of debris by collisions with large debris or other operational space stations through

detailed and conscientious mission planning. DIRECTV has reviewed the list of licensed

systems and systems that are under consideration by the Commission for the nominal 99°

W.L. and 101.6° W.L. orbital location it has requested. In addition, in order to address

non-U.S. licensed systems, DIRECTV has reviewed the list of satellite networks in the

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vicinity of 99° W.L. and 101.6° W.L. for which a request for coordination has been

submitted to the ITU. Only those networks that are operating, or are planned to be

operating, within ± 0.3° have been taken into account in this review.

As a consequence of this review, it has been determined that only two other

systems have been licensed by the Commission for, and are currently operating at, the

nominal 99° W.L. location: SPACEWAY 2 at 99.2° W.L. and GALAXY 16 at 99.0°

W.L. In order to address the resulting physical coordination issue, DIRECTV has applied

for authority to operate DIRECTV 11 at 99.225° W.L. and SPACEWAY-2 at 99.115°

W.L., such that there is no overlap of the station-keeping volumes of these DIRECTV

spacecraft or GALAXY 16 at that position. There are no systems licensed by the

Commission to operate within 0.3° of 101.6° W.L.2

Internationally, the ITU has published requests for coordination of satellite

networks within ±0.3 degrees of 99° W.L. from Canada and the United Kingdom, but has

published no such filings within ±0.3 degrees of 101.6° W.L. DIRECTV can find no

evidence that satellite construction contracts have been awarded for any of these networks,

nor does the Federal Aviation Administration Commercial Space Station Second Quarter

2006 Report show any pending satellite launches for these networks.

2
In addition, DIRECTV and Pegasus have applied for authority to operate satellites at 101°
W.L. in the BSS expansion spectrum when it becomes available in 2007, and those
applications remain pending. See FCC File Nos. SAT-LOA-19970605-00050 (DIRECTV);
SAT-LOA-20020322-00033 (Pegasus). However, those applications are subject to
amendment, and the 101° W.L. location does not fall on the four degree “grid” established by
the Commission. See Establishment of Policies and Service Rules for the Broadcasting
Satellite Service at the 17.3-17.7 GHz Frequency Band and at the 17.7-17.8 GHz Frequency
Band Internationally, and at the 24.75-25.25 GHz Frequency Band for Fixed Satellite
Services Providing Feeder Links to the Broadcasting-Satellite Service and for the
Broadcasting Satellite Service Operating Bi-directionally in the 17.3-17.7 GHz Frequency
Band, 22 FCC Rcd. 8842 (2007).

B-4

Post-Mission Disposal

Consistent with the requirements of Section 25.283(a) of the Commission’s rules,

at the end of the operational life of the satellite, DIRECTV will maneuver DIRECTV 11

into a disposal orbit with an altitude no less than that calculated using the IADC formula:

36,021 km + (1000·CR·A/m).

The calculated value of CRA/m in this instance is based on the following parameters:

CR = Solar Pressure Radiation Coefficient = 1.152

A = Total Solar Pressure Area = 167.6 m2

M = Dry Mass of Satellite = 3556 kg

Using these values in the IADC formula results in a minimum de-orbit altitude of

36075.3 km, or approximately 289 km above geosynchronous altitude. To provide

adequate margin, the nominal disposal orbit will be increased above this calculated value

of 289 km to a value of 350 km. Approximately 1.6 kg of propellant will be allocated

and reserved for final orbit raising maneuvers to this altitude. This value was determined

through a detailed launch vehicle propellant budget analysis. In addition, DIRECTV has

assessed fuel gauging uncertainty and this budgeted propellant provides an adequate

margin of fuel reserve to ensure that the disposal orbit will be achieved despite such

uncertainty.

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Document Created: 2007-10-31 17:33:24
Document Modified: 2007-10-31 17:33:24

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