Searching for Intelligent Life: Understanding Radio Wave Filters

[Entity]

It seems that Earth is constantly being bombarded by radio waves that have been created by natural occurrences.

Concerning the search for intelligent life, what sort of filter is used to disseminate between a naturally occurring radio wave and a radio wave created by intelligent life.

 

[estel]

This is the problem really. Originally, the regular period of pulsars led to them being called "little green men" in the belief that the radio waves were sent by sentient beings, and the original radio sources discovered still carry the LGM label.

 

[ranger]

If other "intelligent beings" wanted to make it easier for us. They could send patterns that would somehow stand out. For example, prime numbers - no known entity generates them naturally. So if we receive radio waves that have a prime number pattern, we can conclude that it must have been sent by another civilization. But of course this would rely on other civilizations being capable of radio astronomy. Note that Earth has only been capable of radio astronomy for a small fraction of its life. And even if we where able to receive such transmissions, the other civilization could have well destroyed themselves by the time we intercept it.

 

[DaveC426913]

SETI@Home used to have pages devoted exactly to the explanation of how they look for signals amongst the noise. I can't seem to find those pages. Asking on their forum will probably get you more info than you could read in a month.

http://setiathome.berkeley.edu/