Elijah Barner

Space Communications Systems

ECET310

7/24/2016

The purpose of this report is to discuss the various communications system that NASA

and other space agency use to communicate with in space. When astronauts have to

communicate with ground control, with satellites, and aboard various spacecraft. While in

space astronauts uses a device called CCA also known as Communications Carrier Assembly.

The CCA also called the “Snoopy Cap is a fabric hat fitted with microphones in the ear for

listening.

The CCA has a boom microphone locate in front of the astronauts mouth for speaking.

Even though NASA uses the CCA they are currently working on developing a new space suit

with a new means of communication. That new project is called ETDP or Exploration

Technology Development Program that is involved with testing various communications

system with the new space suit.

A new form of communication systems also involves the use of laser technology. The

Lunar Laser Communication Demonstration or LLCD was used in a demonstration for 30

days for a possible means of creating a higher board band communication in space. The laser

is capable of reaching over one quarter of million miles and seem to work error free. Another

familiar type of communication system that is well known is satellite communication.

Satellites require amplified radio signals sent by a transponder. When it comes to

communicating with satellites there has to be two channels of communication a transmitter

and a ground receiver.

Satellite is the most common means of communications in space in cellular networks,

space telecom systems, radio transmission, and even television. The important satellite

communication in space is very important when it comes to keep our astronauts inform with

what goes on around them.

CCA also known as the Communications Carrier Assembly typically worn by

astronauts in space. It give them the ability to communicate with each other and ground

control during space missions. No matter where the astronauts are inside or outside of the

space craft. Even if they repairs on the space craft itself they are still able to communicate.

One drawback is the CCA has to be fitted to each astronaut head size.

Neither can the CCA caps be adjusted to fit around the visor or helmet of each

astronaut. For an example if an astronaut is in space and his helmet or microphone shifts it

can cause communication to be demise periodically. The boom microphone can also be an

issues for food consumption and drinking fluids during long-duration of spacewalks.

The newest technology currently being developed by NASA is the LLCD or Lunar

Laser Communication Demonstration. It’s capable of transmitting and receiving signals a

great speed with little or no error during the communication channels. It can download and

upload information at the speed of 622 megabits per second and at 20 megabits per second.

Also it capable at working with any current radio systems today. Don Cornwell the mission

manger state that “Throughout our testing we did not see anything that would prevent the

operational use of this technology in the immediate future”.

But there is promising use for it when NASA Goddard Space Flight Center used the

devices during one of its mission. The mission consisted of LLCD demonstrating error free

communication during broad daylight and even operating with different moon phase and not

having a single error. It also was able to communicate with ground station with wind and

atmospheric turbulence did have any affects.

Also it was able to work with the LADEE or (Lunar Atmosphere and Dust Explorer)

spacecraft and download up to 1 gigabytes of scientific information in less than five minutes.

The only limitation the connection had was the due LADEE spacecraft at 40 megabits per

second. The issue was due to the on board radio system that took a quite a few days to

completely download all of the exact same data. The unique thing about using the LLCD is its

ability to send and receive HD quality video from NASA Administrator Charlie Bolden from

the moon and back to Earth without any interruption.

Satellites communication system are very important to everyday life from GPS, to

meteor logical surveying, and communicating with various ground base antenna giving NASA

mission control information about astronauts. Without various types of satellites today world

would be chaotic and difficult to live in. Because we rely on satellites to navigate us around

the world using GPS. For an example most GPS satellites use NAVSTAR Global Positioning

Systems that provided weather conditions, the location of where the weather is, and for

civilian use for traveling.

Most satellites used in space communication systems on the other hand send radio

waves transmitted to antennas on Earth. The information that is sent is usually is scientific

thing like picture reserved, the present health of the satellite, and where the satellite currently

located in space. The satellites may gather information from celestial object like comets,

asteroids, and even planetary object within range as well. The satellites NASA use have high

power transmitters on their satellites that send signal to their ground based receiver. For an

example to gratify NASA desires for space communication they use several type of

sophisticated networks. The first type DSN or Deep Space Network which is used to provision

all of the scientific spacecraft that gather information from low earth orbit, the edge of the

solar system, and elsewhere in the universe.

The other type of network NASA use is SN or Space Network that is used to provided

tracking and data that is relayed for satellites, spacecraft, and any vehicle other used in space.

The type of vehicle usually are ground based rovers like Curiosity being used on Mars for

exploration of the planetary body.

This is all a part of NASA Space Communications and Navigation or (SCaN) system

that functions as a global radio communication infrastructure.

This is a picture I obtain via the internet showing the various means NASA uses to

communicate with their rover curiosity. The MSL Telecommunication Network use various

sophisticated means to transmit and receive data, commands, and information millions of

miles away for space explorations at ground level on the planet Mars. As you can see it takes

ground antenna to send and receive information to the various satellites on the location of

Curiosity. While the satellites like the bean that information to Curiosity to do various things

like stake picture, retrieve sample on Mars, and explorer the surface of Mars.

References:

http://www.nasa.gov/topics/moonmars/features/hatsman.html

http://www.nasa.gov/content/goddard/laser-demonstration-reveals-bright-future-for-space-

communication

https://www.nasa.gov/directorates/heo/scan/communications/outreach/funfacts/

txt_relay_satellite.html

http://ipnsig.org/2013/07/09/curiosity-rover-the-store-forward-architecture/

http://www2.nict.go.jp/wireless/spacelab/lasersatellitetech/en/04reserch/reseach1.html