GPS Signal Processing[Discussion Thread]

[priyankguddu]

gps signal processing

Hey Guys.. these all days one of the most difficult receiver to design is still GPS receiver for all signal dynamics and approaches..

So lets start a thread for this purpose and add our knowledge into this field

I have a lot to share... Some body just initiate

How about having a detailed discussion on Aquisition and Tracking of GPS signals and processing at all Noise level

Do Post Ideas,,, I will start the thread

 

[spweda]

design of galileo l1f receiver tracking loops

GPS uses spread spectrum and the receiver is just a set of correlators. The challenge is to implement the GPS in the low cost.

 

[priyankguddu]

gps signal matlab code

The real challenge is not only low cost... but the signal processing ,indoor tracking and precise positioning...
I hope this will give u a better idea.

Tracking Sensitivity : -160 dBm
Aquisition :-148 dBm

Positioning < 100 cm

To achieve this a real good signal processing is required thats why its a challenge.. Just imagine signal in indoor is 30-40 dB low.. and lower than noise floor.. Only correlation property and processing gain would not give u this much sensitivity.

This is one aspect... Other can be tracking at very high dynamics and able to give a tradeoff position..

So... I feel a solid Signal processing idea of GPS can give a gr8 insight of all communication system because the requirement posed by GPS reflects a greater deal of knowledge in ESTIMATION THEORY and NOISE analysis.

 

[rag_perfect]

code tracking gps signal receiver matlab code

with the help of GPS and IRNSS..accuracy can be achieved<3m

but BOC correllator has key role in that...

 

[sundarmeenakshi]

gps c/a signal processing gain

with the help of GPS and IRNSS..accuracy can be achieved<3m

but BOC correllator has key role in that...

what is BOc correllator?

 

[priyankguddu]

gps+boc

BOC is Binary offset carrier

Like one used in Galileo system

If one has two carrier one modulated with data and one unmodulated we can do longer coherent signal processing and in turn achieve better accuracy .

Any Body like to start Discussion on TRACKING LOOP Design for GPS

 

[rag_perfect]

boc gps signal

ya sure...
plz give me matlab code if you have
:we are desigining..early late gate disciminator....


thankx...

 

[rag_perfect]

spreading gain gps signal matlab code

hi frnds..
can anybody plz provide me the link from where i can get the matlab source code of Very early – very late correlator used for code tracking of GPS signal of GNSS (Galileo Receiver ANalysis And DesignApplication) project.

its urgently reqd..

plz help..

thankx...

 

[priyankguddu]

signal processing in gps

**Please Press Helped button.."
Hi Rag _

Where in india u r from ?

Exactly I dont have the matlab code..rather I cant share it... but I can give u a link of good paper from which u can implement.

U can search .. university of calagary site i,e
Design of Galileo L1F Receiver Tracking Loops
(URL: http://www.geomatics.ucalgary.ca/links/GradTheses.html)

This has given a gr8 insight of Loops.. I can help u in this,, but cannot share the code hope u understand..

 

[rag_perfect]

thankx priyank..
actuaaly that paper already i have..
but stuck in implementation..

any other programming link can u give..

m from hyderabad...

 

[priyankguddu]

Did U try Matlab file exchange anyways Where r u stuck... I can help u,,, And exactly what type of tracking loops u want to design.. gimme spec..

 

[rag_perfect]

actually we are implenting the code tracking algorithm for BOC signals

we studied very early very late correlator,deconvolution correlator....

in both these correlators differnt procedures are ther to track the code

we implemented the descriminator function as per very early very late correlator....after that we are not able to link: how to design loop filter after discriminator block..
and o/p of loop filter is given to NCO so as to adust the PRN value block...that will subsequeently change the timing index of all five:
veryEarlyIndex,veryLateIndex,earlyIndex, promtIndex,lateIndex.

we stuck here..how to do this??????????

and nothing is given at matlabcentral file exchange...

plz help...