Many adaptations, optimizations, and tests have been left for the further due to lack of time. Further work concerns improvements of electronics, process au-tomation, deeper analysis and covering wider frequency ranges. There are some ideas that I would have liked to try during developing prototype in Chapter 3.
Although the system is tested for a limited range of frequencies from 50kHz to 500kHz and it could cover 90% of the target bandwidth in the design specifi-cation, the device is potentially capable of generating wideband signals includ-ing lower and higher frequencies than 50kHz and 500kHz, respectively.
In addition, the process of analyzing the excitation response and plotting impedance spectra could be automated. Attempts have been made to migrate from several computing stages to an automated and user-friendly interface. But due to time constraint and lack of proper documentation for developing the user interface tool, this process is left for further work.
Several potential causes have been identified and presented in the fishbone diagram to improve the performance of the system. For improving accuracy of the measurement, it is recommended to minimize the crest factor of the re-sponse signal in the interest of using maximum dynamic range of ADC.
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Appendix A
Algorithms
Algorithm 1Wideband Binary Signal Geneartor
1: procedureWIDEBANDBINARYSIGNALGENERATOR(A~I,K,N,~ Opt,Loop Count) 2: ifOpt=Schroederthen
3: Φ~I=P haseGen(Schroeder, ~K)
Algorithm 2Phase Generator
1: procedurePHASEGEN(Opt,K)~ 2: for allk∈(K~Specif ied)do 3: ifOpt=Schroederthen 4: φk=φk−1+ 2πPk−1
2: for allk∈K~Ido .Frequency-domain signal construction 3: Compute:Xd(k) =PN−1
14: forn= 0 : (N−1)do .Quantization:converting to binary signal 15: Compute:xq(n) =Sgn(Re{x(n)})
Algorithm 4Time-domain Frequency-domain swap
1: procedureTFSWAP(A,~ Φ)~
2: fork= 0 : (N−1)do .Frequency-domain signal construction 3: Compute:X(k) =PN−1
8: forn= 0 : (N−1)do .Quantization:converting to binary signal 9: Compute:xq(n) =Sgn(Re{x(n)})
Algorithm 5Power Factor Calculator
1: procedurePFCALC(A,~ K)~