Hi, I am a C beginner and I am trying to write a program for Cellular Demodulator. Can anyone help me?
Thank you.

Only if you can get a helluva lot more specific than that.

if anyone can provide me with a sample C program for wireless communications, for example a modulation or demodulation technique for a BPSK. Thank you

Whee -- we get to play 20 questions!

1. Got any particular hardware in mind?

i didnt get what do u exactly mean by hardware...but m using intel centrino, microsoft vista.....and my C compiler is the LCC compiler

Hey, now we're getting somewhere.

2. What hardware do you expect to perform wirleess communication? Mouse? Keyboard? NIC?

Oops. Is that 4 questions?

OH....no its a PCs or regular cell phone...or actually right now anythg will help me.. I just need to see an example about modulation or demodulation in C.

3. Modulate what?

Ya see, you're not getting that great of answers because you're not asking very good questions, IMO.

From what I gather, you're planning on writing code for a PC. I know of nothing that is not hardware- or OS-specific that would attempt to modulate squat.

I know of algorithms to do some wacky things that may or may not be in the ballpark, but they have gotten nowhere close to fitting the specs you are not describing.

4. Is it a PC?
5. Is it a phone?
6. Where's the wiggly spot?

I am trying to write a program that will b complied on a chip later on, this program will demodulate a received signal from the antenna after being converted from digital to analog waveform. This is Digital and Analog Communications course which is within the electrical department.

So this program will take the outputs of the digital to analog converter, and will try to demodulate it, using a matched filter or correlator, so that it can get the correct message that was transmitted.

All righty. You need to dig into the specs of your "chip" and code to that.

7. What is the micro?

8. Is the ADC/DAC part of the micro or is it an off-chip part?

8-1/2. If off-chip, are you communicating with it via SPI or I2C, etc?

9. What is the development platform on which the code will be compiled?

Actually I am using the lcc compiler, which is basic C programming. Right now I dont need to bother myself with the chip specs or details, all i need to write a small program. The outputs of the A/D converter are handled to me by the instructor, so i dont need to bother again with the analog to digital conevrter...I have the waveforms outputs of the ADC, so i have my digital data, all what i have to do is to demodulate these data and get the BER performance.

10. Any idea where your input magically appears from? Serial port perhaps?

no....the data is generated by a C program written by the teacher. I will have the output data so that i can control my program.

11. So data is coming from a file?

12. And you must read the data from this file (formatted in some way)?

13. And then you need to perform some math on the data?

14. And then you need to output something?

yeah...if you want..we can put it in this way!

15. Do you know the format of the input(s) and that of the expected output(s)?

i dont know yet, but what i really need is if i can find a C program that implements for example a QPSK, BPSK or any other form of modulation. These modulation are used in the Telecommuncation and wireless fields. Thank you.

Yes, I know this. When we grab signals from a phone line, they're fed to an ADC and we get values, perhaps 10 bits of significance, coming in at a rate defined by various registers settings on the micro. We choose to process this data on-the-fly using lookup tables containing frequency information to convolve (I believe) and produce a power level which in turn is also used with various timers and counters to determine whether or not a binary 1 or 0 or some indeterminate noise is currently being detected.

Now, on the other hand, if you have a file containing a canned set of data to which you will need to apply some mathematical function and produce some sort of output text, well, that would be an entirely different animal altogether.

Perhaps if you did some web searching you could feed it all of the information you choose to hide from us and find a solution tailor made to your problem. Most of my annoying little barbs have been designed to try to help you to figure out how to ask a question in a way which can actually produce a usable answer for you.

16. What is your C question?

well my C question is...where can i find an example of QPSK demodulator....i am trying to search the internet..but i cant find it..