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The demand for higher bandwidth has resulted in the development of mm-wave phased array systems. This paper aims to explore a technique that could be used to feed the individual antennas in a mm-wave phased array system with the appropriate phase shifted signal to achieve the required directivity. It presents differential Colpitts oscillators at 5 and 60 GHz that can provide differential output signals to the quadrature signal generators in the proposed phase shifter system.

The phase shifter system comprises a differential Colpitts voltage controlled oscillator (VCO) and utilizes the vector-sum technique to generate the phase shifted signal. The differential VCO is connected in the common-collector configuration for the 5-GHz VCO, and is extended using a cascode transistor for the 60-GHz VCO for better stability at mm-wave. The vector sum is achieved using a variable gain amplifier (VGA) that combines the in-phase and quadrature phase signal, generated from oscillator output using hybrid Lange couplers. The devices were fabricated using IBM 130-nm SiGe BiCMOS process, and simulations were performed with a process design kit provided by the foundry.

The measured results of the 5-GHz and 60-GHz VCOs indicate that differential Colpitts VCO could generate oscillator output with good phase noise performance. The simulation results of the phase shifter system indicate that the generation of signals with phases from 0° to 360° in steps of 22.5° was achieved using the proposed approach. A Gilbert mixer topology was used for the VGA and the linearity was improved by a pre-distortion circuit implemented using an inverse tanh cell.

The measurement results indicate that differential Colpitts oscillator in common-collector configuration could be used to generate differential VCO signals for the vector-sum phase shifter. The simulation results of the proposed phase shifter system at mm-wave show that the phase shift could be realised at a total power consumption of 200 mW.

This work aims to improve upon the linearity of integrated CMOS current sensors used in switch mode power supply topologies, using a low-cost and low-voltage (less than 1.2 V) CMOS technology node. Improved sensor accuracy contributes to efficiency in switched supplies by reducing measurement errors when it is integrated with closed-loop control.

Integrated current-sensing methods were investigated and CMOS solutions were prioritized. These solutions were implemented and characterized in the desired process and shortcomings were identified. A theoretical analysis accompanied by simulated tests was used to refine improvements which were prototyped. The current sensor prototypes were fabricated and tested.

Measured and simulated results are presented which show improved linearity in current sensor outputs. Techniques borrowed from analog amplifier design can be used to improve the dynamic range and linearity of current-steered CMOS pairs for measuring current. A current sensor with a gain of 5 V/A operating in a 10 MHz switch mode supply environment is demonstrated.

This paper proposes an alternative approach to creating suitable bias conditions for linearity in a SenseFET topology. The proposed method is compact and architecturally simple in comparison to other techniques.

The 60 GHz unlicensed band is being utilized for high-speed wireless networks with data rates in the gigabit range. To successfully make use of these high-speed signals in a digital system, a high-speed analog-to-digital converter (ADC) is necessary. This paper aims to present the use of a common collector (CC) input tree and Cherry Hooper (C-H) differential amplifier to enable analog-to-digital conversion at high frequencies.

The CC input tree is designed to separate the input Miller capacitance of each comparator stage. The CC stages are biased to obtain bandwidth speeds higher than the comparator stages while using less current than the comparator stages. The C-H differential amplifier is modified to accommodate the low breakdown voltages of the technology node and implemented as a comparator. The comparator stages are biased to obtain a high output voltage swing and have a small signal bandwidth up to 29 GHz. Simulations were performed using foundry development kits to verify circuit operation. A two-bit ADC was prototyped in IBM’s 130 nm SiGe BiCMOS 8HP technology node. Measurements were carried out on test printed circuit boards and compared with simulation results.

The use of the added CC input tree showed a simulated bandwidth improvement of approximately 3.23 times when compared to a basic flash architecture, for a two-bit ADC. Measured results showed an effective number of bits (ENOB) of 1.18, from DC up to 2 GHz, whereas the simulated result was 1.5. The maximum measured integral non-linearity and differential non-linearity was 0.33 LSB. The prototype ADC had a figure of merit of 42 pJ/sample.

The prototype ADC results showed that the group delay for the C-H comparator plays a critical role in ADC performance for high frequency input signals. For minimal component variation, the group delay between channels deviate from each other, causing incorrect output codes. The prototype ADC had a low gain which reduced the comparator performance. The two-bit CC C-H ADC is capable of achieving an ENOB close to 1.18, for frequencies up to 2 GHz, with 180 mW total power consumption.

The purpose of this paper was to present the results of the three types of FG transistors that were investigated. The reliability issues of oxide thickness due to programming, fabrication defects and process variation may cause leakage currents and thus charge retention failure in the floating gate (FG).

The tunnelling and electron injection methods were applied to program FG devices of different lengths (180 and 350 nm) and coupling capacitor sizes. The drain current and threshold voltage changes were determined for both gate and drain voltage sweep. The devices were fabricated using IBM 130 nm process technology.

Current leakages are increasing with device scaling and reducing the charge retention time. During programming, charge traps may occur in the oxide and prevent further programming. Thus, the dominant factors are the reliability of oxide thickness to avoid charge traps and prevent current/charge leakages in the FG devices. The capacitive coupling (between the tunnelling and electron injection capacitors) may contribute to other reliability issues if not properly considered.

Although the results have raised further research questions, as revealed by certain reliability issues, they have shown that the use of FGs with nanoscale technology is promising and may be suitable for memory and switching applications.

Discussion of the case will enable the students to: ● use “Strengths, Weaknesses, Opportunities, and Threats” analysis. ● Use “pros and cons” analysis. ● Explain what constitutes an effective strategy. ● Analyze the quality of the strategy for IndiGo Airlines (IA). ● Explain sustained competitive advantage through value, rareness, imitability and organization framework.

This case describes a situation in which InterGlobe Aviation Ltd. (IGAL) has been experiencing multiple engine snags because of the faulty Pratt and Whitney engines. In a span of two years between June 2018 and January 2020, IGAL faced around 22 snags. IGAL is known to be one of the safest airlines in the world, the engine issue has tainted its reputation. In October 2019, in just one week IA faced four-engine snags, forcing the Directorate General of Civil Aviation (DGCA) to come out with a guideline in November 2019. The faulty engines were to be replaced by January 31, 2020. If IA failed to complete the task by the given deadline then IA would have to ground around 70–80 aircraft. IA was way behind the deadline when on January 13, 2020, they received an email from DGCA mentioning an extension of the deadline to May 31, 2020. The purpose of this case is to provide an opportunity for the participants to take into consideration the data given for IA and make assumptions and resolve the dilemma through which Ronojoy Dutta (Dutta), the Chief executive officer if IA is going through.

The case engages the participants in deciding a suitable course of action for IA to develop a strategy and is ideal to teach elements of strategy. The case can be used in the following courses/programs: ● A strategy formulation module in strategic management program or post-graduate program in management.

Teaching Notes are available for educators only.

CSS 11: Strategy.

Teaching Notes are available for educators only.

The purpose of this paper is to develop a framework to understand how bottom of the pyramid (BoP) retailers adopt brands who sell to a very different set of customers and are served through long indirect channels.

In this study, 60 retailers belonging to different villages of Central and North Gujarat were interviewed. The interviews were audio recorded, transcribed and analyzed. A grounded theory-based analysis was carried out.

The analysis brought out six criteria used by the retailers in selecting brands with demand for the brand as the most dominant factor. Other criteria included brand adoption by other retailers, profitability, influence of wholesaler/distributor and packaging.

Previous studies with regard to brand adoption by retailers have focused on large retailers who are approached directly by the brands. There is a lack of studies on how BoP retailers adopt brands. Most studies have approached the subject from a distribution perspective of reaching these markets.

This paper focuses on the use of e-resources by research scholars and post-graduate students at Kashmir University. The main aim is to determine the use of e-resources, users skills in handling e-resources and the purpose of their use. Further, this paper aims to highlight the problems faced by research scholars and post-graduate students in accessing e-resources.

The survey was conducted through a structured questionnaire circulated among 250 research scholars, both (M.Phil./Ph.D.) and post-graduate students, from different departments of Kashmir University, and the response rate was 80%. Random sample method was used for the selection of respondents and interacting with them. The responses received from the research scholars to 14 questions are presented in the form of tables.

Major findings of the study reveal that the majority of the students reported using electronic journal resources for various purposes including working on assignments, research proposal writing, literature review writing, research report writing, current awareness and leisurely exploration of ongoing scientific debates through peer-reviewed papers. The challenges encountered in the use of electronic journal resources include a power outage, inadequate bandwidth, slow download speed, inability to access the resources from home, lack of training, lack of awareness, limited access to computers and difficulty in searching. The paper concludes that electronic resources have become an integral part of the information needs of research scholars’ post-graduate students at Kashmir University. Further, it finds that e-resources can be good substitutes for conventional resources, if the access is fast, and more computer terminals are installed to provide fast access to e-resources. Finally, recommendations for improving the use of electronic journal resources are provided.

The paper restrains the study exclusively to use of e-resources by the research scholars and post-graduate students of Kashmir University.

The paper highlights the use of e-resources by research scholars and post-graduate students of Kashmir University and makes some constructive suggestions for the improvement of electronic resources and services. This is the first time an effort has been made to assess the use of electronic resources by post-graduate students at Kashmir University. The study could be used to assess the post-graduate students’ needs for electronic resources at the Kashmir University and other users in higher learning institutions.

Data science industry is a multidisciplinary field that deals with a large amount of data and derives useful information for taking routine and strategic business decisions. The purpose of this article is to examine the relationship between pricing models, engagement models, and firm performance (FP). This study also aims at uncovering the most effective pricing model and engagement model for improving FP.

Indian data scientists were the respondents of the study. A total of 213 responses were carefully chosen. The data were analyzed using structural equations on Statistical Package for Social Sciences-Analysis of Moment Structures (SPSS-AMOS) version 25 software.

The findings of the study suggested the positive and significant impact of pricing models and engagement models on FP. Value-based pricing strategies have the maximum impact on FP. On the other hand, managed services have a higher influence on FP.

By developing a multi-faceted framework, this study is a novel contribution to the field of business strategy, especially for the data science industry.

The aim of this study is to understand a family firm's choice of related-party transaction (RPT) types and analyze their value impacts to separate the abusive from benign RPTs.

It uses a 10-year panel of BSE-listed 378 family (and 200 non-family) firms. The fixed effects, logit and difference-in-difference (DID) models help examine value effects, propensity and persistence of harmful RPTs.

Loans/guarantees (irrespective of counterparties) destroy firm value. Capital asset RPTs decrease the firm value but enhance value when undertaken with holding parties. Operating RPTs increase firm value and profitability. They improve asset utilization and reduce discretionary expenses (especially when made with controlled entities). Family firms have larger loans/guarantees and capital asset volumes but have smaller operating RPTs than non-family firms. They are less likely to undertake loans/guarantees (and even operating RPTs) and more capital RPTs vis-à-vis non-family firms. Family firms persist with dubious loans/guarantees but hold back beneficial operating RPTs, despite RPTs being in investor cross-hairs amid the Satyam scam.

Rent extractability and counterparty incentives supplement each other. (1) The higher extractability of related-party loans and guarantees (RPLGs) dominates the lower extraction incentives of controlled parties. (2) Holding parties' bringing assets, providing a growth engine and adding value dominate their higher extraction incentives (3) The big gains to the operational efficiency come from operating RPTs with controlled parties, generally operating companies in the family house. (4) Dubious RPTs seem more integral to family firms' choices than non-family firms. (5) Counterparty incentives behind the divergent use of RPTs deserve more research attention. Future studies can give more attention to how family characteristics affect divergent motives behind RPTs.

First, the study does not single out family firms for dubious use of all RPTs. Second, investors, auditors or creditors must pay close attention to RPLGs as a special expropriation mechanism. Third, operating RPTs (and capital RPTs with holding parties) benefit family firms. However, solid procedural safeguards are necessary. Overall, results may help clarify the dilemma Indian regulators face in balancing the abusive and business sides of RPTs.

The study fills the gap by arguing why some RPTs may be dubious or benign and then shows how RPTs' misuse depends on counterparty types. It shows operating RPTs enhance operating efficiencies on several dimensions and that benefits may vary with counterparty types. It also presents the first evidence that family firms favor dubious RPTs more and efficient RPTs less than non-family firms.

This paper inspects in detail the seasonality (deterministic) in container freight rates, and compares seasonality patterns in different freight rate indices. A deterministic seasonality unit root test is performed to achieve set objectives. This study concludes that all the indices (tested in this paper) exhibit significant deterministic seasonality. For January and August, there is no seasonal effect observed in all five series. At the same time, all the indices except Exports from Europe Rate Index (EEI) exhibit significant seasonal patterns in February, September, and December. All five indices exhibit significant seasonality during May, and the coefficient sign shows a drop in the freight rates. During March, October, and November; it is observed that only EEI exhibit significant seasonal patterns. The results could be beneficial for carriers and agents who are involved in the containerised freight transport business. Also, shippers could get a clear idea about the freight rates' nature across various trade routes.