Comparator redundancy in flash-based pipeline ADCs. If however the comparison operation is spread over several clock cycles, the number of comparators required per clock cycle can be significantly reduced. Several advantages of the new system are investigated. The coupling results in the LO signal getting multiplied with itself and gives a DC signal.
Such a receiver contains two sections, each section consisting of an image reject filter, mixer and low pass filter. Another emerging trend is the rising demand for high-speed low-power analog-to-digital converters ADCs to accommodate the increased use of digital Flash adc thesis and big data.
Figure a shows the block diagram of such a receiver.
A comparative analysis of the three architectures is given at the end of this chapter The list of publications that were used as reference for this work is given at the end of the thesis.
Dean, School of Graduate Studies this thesis. It is concluded that the folding and interpolation system in the video band achieves an even better performance than full-parallel converters implemented in a similar process and dissipating over 10 W.
Cyclic or algorithmic can be seen as a pipeline structure with. Flash adc thesis HF must have a very high Q up to 50 and more and it must have an order which is high enough; and in some cases, the center frequency must be tunable.
Figure b shows the IF downconversion scheme in the frequency domain. Next, the proposed complex image reject filter architecture is discussed. A good choice of the sampling frequency accommodates an optimized implementation of the down conversion mixer.
Thanks to many of my close friends who helped keep my morale high throughout this period. A complex summation of the I and Q components yields the desired signal. He received the Ph. Thanks to her for being such a lovely child.
Thanks for your support and the camaraderie. This thesis presents the style of a 7-bit 2. This helps in having relaxed specifications for the analog blocks preceding the modulator.
This makes the low-IF receiver another good candidate for monolithic implementation of receivers. This architecture has been successfully implemented in a single chip receiver. Hence, to prevent corruption of the RF signal, a prefiltering of the signal needs to be performed before the mixing operation.
The Academic Faculty by. This is due to the sequential structure shown in Fig. The low pass filters can be implemented as analog integrated filters.
The subject of his M.
Structure of the pipeline analog to digital converter. Here, the complex sum of the quadrature LO mixer outputs have impulse functions at both c and -c; the one at c being due to non-ideality in the phase relationships between the sine and the cosine outputs of the local oscillator.
Due to the hybrid architectural structure, the offset requirement for the flash ADC is more stringent than for a conventional standalone 3-bit ADC.
However, a fixed choice of down conversion frequency with respect to the sampling rate poses certain restrictions on the overall system design.
We ensured to draw in experienced and gifted authors and provide rewarding working problems that motivate these to do their finest work with each order.
Yoo, Jincheol; Graduate Program: And finally, thanks to little Diya who came to our world halfway through my MS and transformed our home into an unending source of joy.
PhD approval eventually came but the group I was working for had ceased to exist and Dr group, the periods of discourse over circuit and layout techniques were always very. Measurements of a prototype chip show that the ENOB improves from 3. Seyedeh The dissertation of Seyedeh Sedigheh Hashemi is approved.
The architecture is further optimized and variations to the main structure are proposed in the later sections of the thesis. At the same time, the problems of DC offset and flicker noise of the zero-IF receiver does not arise in the low-IF case. It achieves an excellent performance while dissipating only mW from a single 5-V power supply.
The low-IF receiver using complex bandpass 24 converter is the architecture used in the receiver discussed in the thesis. A few areas for future scope of work in the same field are proposed in the end.Professor Dejan Marković, Chair Low-power and low-area flash ADC architectures are extremely susceptible to offset variations, and a calibration technique to alleviate this effect is necessary.
Moved Permanently. The document has moved here. iii DESIGN OF RSD-CYCLIC AND HYBRID RSD-CYCLIC/SIGMA-DELTA ADCs I have examined the final copy of this dissertation for form and content, and recommend that it. such ADCs designed in CMOS 90nm technology are presented in this thesis. In flash ADC, thermometer to binary encoder often becomes bottleneck in achieving high speed.
An encoder deploying new CMOS logic, with fewer transistors through the use of pseudo-dynamic circuits is described. This 4 bit flash ADC operates at 5GHz with an. In a flash ADC, quantization level errors mostly come from resistor mismatches in the resistor reference ladder which exhibits spatial gradient distribution with non-zero mean offsets and from comparator input offsets mainly due to transistor threshold.
The Thesis Committee for Arnab Kumar Dutta certiﬁes that this is the approved version of the following thesis: Design of a Time-based Sigma-Delta Modulator.Download