Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

A question of transceiver

Status
Not open for further replies.

OMEsystem

Advanced Member level 4
Joined
Dec 1, 2005
Messages
102
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,296
Activity points
2,061
I have a question of the slides in this link.
Pleae go to page 41.

**broken link removed**

I can't realize what's the relation between "small antenna" and "LNA sensitivity", and
the realation between "small antenna" and "IIP3".

Any recommendation?

Thanks,
 

biff44

Advanced Member level 5
Joined
Dec 24, 2004
Messages
4,992
Helped
1,372
Reputation
2,740
Reaction score
1,045
Trophy points
1,393
Location
New England, USA
Activity points
37,576
It seems like he is saying the following:

If you build a reciever with high sensitivity, you will not need much antenna gain, so the antenna can be small.

If you build a receiver with higher selectivity, you will be able to use components that generate more spurs, since the selectivity will filter the unwanted spurious signals out.

lower Power Diss = Lower battery lifetime, obviously.

AGC 20 dB, who knows?

If you build a receiver that has high IIP3 (does not readily generate out of band spurious, like 2-tne third order products) you do not need an antenna with high directivity, so the antenna can be small. An omnidirectional antenna is small, but will let in interfering signals from all directions, so the receiver must be able to handle those interfering signals without spectrally regrowing into the recievers IF frequency band.
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top