Hi. I need some help with my project. Money is not the problem, but I need someone really expert in Matlab Simulink who will help me to finish this project. Of course I will help and follow your work day by day and explain you everything you don't understand. It will be a very long work (I think) but I'll pay very well.
The project consists in a simulation in Simulink of a high speed communication using the MIMO technique in addition to multichannel frequency multiplexing. I've attached an important paper that you have to read about multichannel frequency multiplexing.
In practice I want to simulate the system presented and make it better by using MIMO combined to it!!!
The goal is to have a running simulation with BER nearly 0. You have to modify the simulation I've started and make it work!
This are the datas of the problem:
- the transmission is LOS and the frequency bands are the 2 slots [81-86 GHz] and [94.1-100 GHz].
- Multichannel frequency division multiplexing and LDPC codes are used.
- the modulation used is a 64-QAM with raised cosine transmit filter (rolloff = 0.25).
- the spectral efficency is 4,8 bps/Hz (E=k/1+rolloff) where k=log2(64)=6
- the transmission distance is 100m
- the antenna gains are respectively 24dBi in transmission (horn antennas) and 40dBi rx (cassegrainian antennas).
- atmospheric attenuation -> ITU models -> 20dB for 99% reliability
- the receiver figure is 6dB
- the maximum transmission power is 100mW (20dBm)
All this date are necessary to calculate the link budget (already done), I can provide the calcs and I'm happy if you can provide yours in order to verify!
My calcs report that the transmission is possible with Eb/No= 19dB and a BER= 10^-5
The boost in the bitrate is obtained with MIMO techniques, in particular with a 4x4 configuration and spatial multiplexing.
This means that the source stream is divided into 4 different streams transmitted by 4 different antennas. Each rx antenna is receiving all the transmission, so we need to implement an alghoritm to separate and receive the different streams. This is the real problem. The algorithm must be written in Matlab. An example is the V-Blast algorithm that I attached.
STRUCTURE OF THE SIMULATION
Attached you can find the beginning of my simulation. It's just a start and the MIMO algorithm is not implemented. At this point every rx antenna receives only one stream. Of course only 2 trasmitters are present and not 4!
I'm asking you to upgrade this simulation as requested.
You have to run the parameters initialization file first (.m file).
Structure of the requested simulation
The unique bit source is divided into 16 different streams (in the simulation we have just 2 and with 2 different sources). Each stream is LDPC coded. The LDPC simulink block has the DVBS2 parity check matrix (32400x64800) as a parameter which has a coderate of 1/2.
Each stream goes through a 64-QAM modulation and a raised cosine transmit filter. After that (IMPORTANT POINT) the signals are upconverted at an intermediate frequency (ex. 2GHz) in adjacent bands occupying 560MHz each as in the paper that I attached (Improved Spectral Efficiency...).
After that the signals are grouped in groups of 4 by a combiner becoming 4 signals (each one composed by 4 adjacent signals). At this point we've the final 4 upconversions (all at the same frequency) in order to fit the 2 bandwith slots [81-86 GHz] and [94.1-100 GHz]. In this way all the 4 antennas transmit at the same frequency and MIMO can be used.
The rx chain is the inverse of the transmission one, but as I said, an algotithm for the 4x4 MIMO detection must be implemented. All the rx antennas must rx all 4 transmissions and separate it!
After that we have to consider other interference problems and add it to our simulation, such as phase noise.
If you think you are able to help me doing the whole work or just for the 4x4 MIMO algorithm, contact me.
You also have to explain me your work!