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Description
As integrated technologies are scaling down, there is an increasing trend in the

process,voltage and temperature (PVT) variations of highly integrated RF systems.

Accounting for these variations during the design phase requires tremendous amount

of time for prediction of RF performance and optimizing it accordingly. Thus, there

is an increasing gap between the need

As integrated technologies are scaling down, there is an increasing trend in the

process,voltage and temperature (PVT) variations of highly integrated RF systems.

Accounting for these variations during the design phase requires tremendous amount

of time for prediction of RF performance and optimizing it accordingly. Thus, there

is an increasing gap between the need to relax the RF performance requirements at

the design phase for rapid development and the need to provide high performance

and low cost RF circuits that function with PVT variations. No matter how care-

fully designed, RF integrated circuits (ICs) manufactured with advanced technology

nodes necessitate lengthy post-production calibration and test cycles with expensive

RF test instruments. Hence design-for-test (DFT) is proposed for low-cost and fast

measurement of performance parameters during both post-production and in-eld op-

eration. For example, built-in self-test (BIST) is a DFT solution for low-cost on-chip

measurement of RF performance parameters. In this dissertation, three aspects of

automated test and calibration, including DFT mathematical model, BIST hardware

and built-in calibration are covered for RF front-end blocks.

First, the theoretical foundation of a post-production test of RF integrated phased

array antennas is proposed by developing the mathematical model to measure gain

and phase mismatches between antenna elements without any electrical contact. The

proposed technique is fast, cost-efficient and uses near-field measurement of radiated

power from antennas hence, it requires single test setup, it has easy implementation

and it is short in time which makes it viable for industrialized high volume integrated

IC production test.

Second, a BIST model intended for the characterization of I/Q offset, gain and

phase mismatch of IQ transmitters without relying on external equipment is intro-

duced. The proposed BIST method is based on on-chip amplitude measurement as

in prior works however,here the variations in the BIST circuit do not affect the target

parameter estimation accuracy since measurements are designed to be relative. The

BIST circuit is implemented in 130nm technology and can be used for post-production

and in-field calibration.

Third, a programmable low noise amplifier (LNA) is proposed which is adaptable

to different application scenarios depending on the specification requirements. Its

performance is optimized with regards to required specifications e.g. distance, power

consumption, BER, data rate, etc.The statistical modeling is used to capture the

correlations among measured performance parameters and calibration modes for fast

adaptation. Machine learning technique is used to capture these non-linear correlations and build the probability distribution of a target parameter based on measurement results of the correlated parameters. The proposed concept is demonstrated by

embedding built-in tuning knobs in LNA design in 130nm technology. The tuning

knobs are carefully designed to provide independent combinations of important per-

formance parameters such as gain and linearity. Minimum number of switches are

used to provide the desired tuning range without a need for an external analog input.
ContributorsShafiee, Maryam (Author) / Ozev, Sule (Thesis advisor) / Diaz, Rodolfo (Committee member) / Ogras, Umit Y. (Committee member) / Bakkaloglu, Bertan (Committee member) / Arizona State University (Publisher)
Created2018
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Description
The presence of expansive soils underneath pavement structures is considered one of the most common sources of pavement distresses, due to differential settlements caused by differential moisture distribution attributed to soil heterogeneity and seasonal climatic fluctuations. The cost of the repairs to the infrastructure caused by expansive soils is estimated

The presence of expansive soils underneath pavement structures is considered one of the most common sources of pavement distresses, due to differential settlements caused by differential moisture distribution attributed to soil heterogeneity and seasonal climatic fluctuations. The cost of the repairs to the infrastructure caused by expansive soils is estimated to exceed 10 billion dollars annually in the US, as reported by Puppala and Cerato (2009). Although many studies have been developed to better understand the volume change of unsaturated soils and incorporate the effect of swelling/shrinkage behavior into pavement design procedures, current methodologies are still based on simple correlations with index properties or other empirical methods. Such solutions lead to poor or uneconomical design practices. The objective of this study was to calibrate and implement a new mechanistic, stochastic model that predicts pavement distresses caused by the presence of expansive soils. Three major tasks were completed to fulfill the objective of this study: 1) a laboratory research program performed to estimate the volume change of compacted specimens, with different expansion potential, due to the simultaneous application of suction and net normal stresses, 2) the calibration of a new mechanistic free-swell model for expansive soils tailored to pavement structures, based on elevation information collected from the Long Term Pavement Performance (LTPP) program, and 3) the incorporation and calibration of the free-swell stochastic model results into the current Pavement Mechanistic-Empirical (ME) Design procedure using the International Roughness Index (IRI) models. The results presented includes: 1) an empirical model to estimate volume change due to the coupled effect of suction, and net normal stresses, for soils with different soil index properties, 2) a calibrated model to adjust the free-swell results of the mechanistic-stochastic model developed by Olaiz et al. (2021), and 3) an updated IRI equation for asphalt concrete pavements to account for volume change fluctuations due to changes in suction stress conditions. The models presented can be easily implemented into currently available pavement design procedures and greatly improves over the existing empirical models that have been used for more than four decades.
ContributorsMosawi, Mohammad (Author) / Zapata, Claudia E (Thesis advisor) / Kavazanjian, Edward (Committee member) / Kaloush, Kamil E (Committee member) / Arizona State University (Publisher)
Created2022