Continue to Site

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.

Register Log in

Pseudo-random sequence and pilots

Status
Not open for further replies.
A

Antonio_Magma

Full Member level 2
Joined
Jun 21, 2005
Messages
136
Helped
3
Reputation
6
Reaction score
2
Trophy points
1,298
Activity points
2,777
Hi, i'm doing a project on OFDM and currently i'm just playing around and exploring with the HiperLan/2 demo that comes together with Simulink.

I noticed at OFDM transmission, pilots are inserted and these pilots are single sample data inserted regularly btwn the actual data. These pilots are generated by a Pseudo-random binary generator block.

What is this block? And why do we use this block to generate the pilots?
 

PseudoRandom Binary generator is nothig but a shift register which will output the sequence of 1s and 0s. This sequence (called a PN sequence) has a random nature ; that is it does not repeat itself. (Well it repeats itself but after a very very long time so that it can be considered as random. Theoretically it repeats after an infinite amount of time.)

Pilots are mapped with PN sequence to provide security. Since the sequence is not repeatative, it is nearly impossible to know ad generate the sequece.
 

yes it provides security as it will prevent a hacker from deciphering the pilot (known sequence) hence he cannot find the channel conditions and this prevents him from synchronizing to the unknown data stream..
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top