Antenna - Theory .com: The Antenna Site

Antenna Basics Antenna Types Smith Charts Antenna Measurements

antenna-theory.com :: View topic - 2.4 Ghz receiving antenna
antenna-theory.com Forum Index antenna-theory.com
Antenna Theory
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

2.4 Ghz receiving antenna

 
Post new topic   Reply to topic    antenna-theory.com Forum Index -> Questions Related to Antenna Theory
View previous topic :: View next topic  
Author Message
btb4198
Antenna Theory Regular


Joined: 19 May 2011
Posts: 20

PostPosted: Sun May 22, 2011 8:18 pm    Post subject: 2.4 Ghz receiving antenna Reply with quote

I have designed a 2.4 Ghz receiving antenna. Do I need a Narrow (Single Frequency) Band Pass Filter after the antenna to filter out noise or does the antenna only work for 2.4 Ghz?
Back to top
View user's profile Send private message
admin
Site Admin


Joined: 03 Jan 2007
Posts: 197

PostPosted: Mon May 23, 2011 5:09 am    Post subject: Reply with quote

The receiver you use should already have any necessary filters built into it.

As for whether copper wires will work as transmission lines: no, the characteristic impedance will vary wildly. You'll need to keep the transmission line length to under 1-2 cm (0.1 wavelengths) or you should use some RF transmission line cable (such as a 50 Ohm coaxial cable). See the transmission line tutorial for more info.

Also, try to keep all your posts on this topic to a single thread, it will make the discussion more coherent.
Back to top
View user's profile Send private message Send e-mail
btb4198
Antenna Theory Regular


Joined: 19 May 2011
Posts: 20

PostPosted: Mon May 23, 2011 12:42 pm    Post subject: Reply with quote

do most receiver have a built into op amp ?

I mean can they really run off 7.1950E-8 [watts]?
Back to top
View user's profile Send private message
Schubert
Antenna Wizard


Joined: 08 Apr 2009
Posts: 161

PostPosted: Tue May 24, 2011 4:05 am    Post subject: Reply with quote

Most receivers do have some sort of low-noise amplification. I'm not sure what the gain of the amplifiers are though.

7.19e-8 W sounds low, but it is not. Note that wifi receivers having a sensitivity of -70 dBm is not uncommon. This is -100 dB, which is 10^-10 W. So you actually have more than 100 times enough power.
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    antenna-theory.com Forum Index -> Questions Related to Antenna Theory All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group