Analyzing the spatial spectrum and tuning the antenna
A project usually consists of reading papers on a chosen topic, comparing performances of different approaches, perhaps proposing your own algorithms/improvements, and implementing one or two of them.
Project Proposal – MIMO Antennas (Fidelity Effects via Adaptive Array Antennas)
There are multiple ways to implement smart antennas. This paper will be focused primarily on how using multiple input multiple output (MIMO) technology can increase the fidelity of signals. This process is done by analyzing the spatial spectrum and tuning the antenna accordingly. The antenna is tuned by steering the beam into the direction of interest and attenuating all other interfering signals including noise.
These antenna arrays locate the desired signals by determining the direction of arrival (DOA) and using this information to calculate beam forming vectors. This information would then be processed so that the antenna knows where to focus and can track a mobile target e.g. a satellite. If a single antenna were to try and communicate with the same satellite it would have to make a compromise between fidelity and the expense of more signal processing. This will be something we will test using Mat lab; where we will simulate a mimo antenna vs a standard antenna and see how the fidelity compares to each, and then take into consideration how the smart antenna can simultaneously process the desired signal and track it.
An important thing to note is that the multiple antennas used in MIMO technology are applied at both the transmitter and receiver end of communication systems. Our primary concern will be testing the Fidelity Factor (FF) which is basically the similarity between transmitted and received signals; Ideally FF is one meaning there is no fidelity loss. The System Fidelity Factor (SFF) is what we think will make the MIMO antenna much better than a standard single antenna; this can be tested in HFSS and Matlab and also calculated. See the equation below for how fidelity of an antenna can be calculated.
Figure 1: Shows the equation for fidelity of a given antenna using the normalized signals to factor out scaling effect and time delay.
An example where fidelity importance can be seen is in DX engineering: using a repeater system on two meter, where if a signal with low fidelity is to be transmitted from the repeater and in addition to typical path loss the signal will require more processing to restore its original pulse shaping, which could have been avoided if the FF were closer to one. MIMO has an advantage for maximizing fidelity by using spatial information processing techniques like spatial multiplexing and proper beam forming.
Reports must include the following parts:
-Project title and group members
-Abstract – A paragraph that summarizes the problem and the results.
-Introduction – Sets the context, describes the problem, and describes your solution.
-Description – One or more sections that describes the problem and your approach to the solution in detail.
-Evaluation – A section that quantitatively evaluates your ideas.
-Related work – Describes representative works related to your work, and summarizes the pros and cons of each work.
-Summary and Conclusions – Summarize what you did and what interesting things you learned from the project.
-Reference list – Matlab codes (if available): List all the Matlab codes written by you. if you use codes from others, make sure that you cite them appropriately.
References:
1. DOA and Beam forming signal processing technique with multi array system.
http://www.vissta.ncsu.edu/publications/ahk/spm1996.pdf
“Two Decades of Array Signal Processing Research” by Hamid Krim and Mats Viberg in IEEE Signal Processing Magazine, July 1996
2. Antenna fidelity
https://www.feko.info/applications/white-papers/time-analysis-of-UWB-antenna/uwb-monopole-antenna/view
“Time Analysis of UWB Antennas.” Feko.info. N.p., n.d. Web. 08 Oct. 2016.
3. Wideband MIMO antenna
http://publications.lib.chalmers.se/records/fulltext/199329/local_199329.pdf Al-Rawi, A.; Hussain, A.; Yang, J. (2014) “A new compact wideband MIMO antenna – the double-sided tapered self-grounded monopole array”. IEEE Transactions on Antennas and Propagation, vol. 62(6), pp. 3365 – 3369.
