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The purpose of this paper is to implement a highly linear 180 nm complementary metal oxide semiconductor (CMOS) power amplifier (PA) to meet the stringent linearity requirement of an long term evolution (LTE) signal with minimum trade-off to power added efficiency (PAE).

The CMOS PA is designed in a cascaded dual-stage configuration comprises a driver amplifier and a main PA. The gate voltage (VGS) of the driver amplifier is tuned to optimize its positive third-order transconductance (g_m3) to be canceled with the main PA’s fixed negative g_m3. The g_m3 cancellation between these stages mitigates the third-order intermodulation product (IMD3) that contributes to enhanced linearity.

For driver’s VGS of 0.82 V with continuous wave signal, the proposed PA achieved a power gain of 14.5 dB with a peak PAE of 31.8% and a saturated output power of 23.3 dBm at 2.45 GHz. A maximum third-order output intercept point of 34 dBm is achieved at 20.2 dBm output power with a corresponding IMD3 of −33.4 dBc. When tested with a 20 MHz LTE signal, the PA delivers 19 dBm maximum linear output power for an adjacent channel leakage ratio specification of −30 dBc.

In this study, a novel cascaded g_m3 cancellation technique has been implemented to achieve a maximum linear output power under modulated signals.

The purpose of this paper is to introduce a new linearization technique known as the passive linearizer technique which does not affect the power added efficiency (PAE) while maintaining a power gain of more than 20 dB for complementary metal oxide semiconductor (CMOS) power amplifier (PA).

The linearization mechanism is executed with an aid of a passive linearizer implemented at the gate of the main amplifier to minimize the effect of C_gs capacitance through the generation of opposite phase response at the main amplifier. The inductor-less output matching network presents an almost lossless output matching network which contributes to high gain, PAE and output power. The linearity performance is improved without the penalty of power consumption, power gain and stability.

With this topology, the PA delivers more than 20 dB gain for the Bluetooth Low Energy (BLE) Band from 2.4 GHz to 2.5 GHz with a supply headroom of 1.8 V. At the center frequency of 2.45 GHz, the PA exhibits a gain of 23.3 dB with corresponding peak PAE of 40.11% at a maximum output power of 14.3 dBm. At a maximum linear output power of 12.7 dBm, a PAE of 37.3% has been achieved with a peak third order intermodulation product of 28.04 dBm with a power consumption of 50.58 mW. This corresponds to ACLR of – 20 dBc, thus qualifying the PA to operate for BLE operation.

The proposed technique is able to boost up the efficiency and output power, as well as linearize the PA closer to 1 dB compression point. This reduces the trade-off between linear output power and PAE in CMOS PA design.

The proposed CMOS PA can be integrated comfortably to a BLE transmitter, allowing it to reduce the transceiver’s overall power consumption.

The purpose of this paper is to examine the effect of perceived quality on intention to revisit coffee concept shops among regular and irregular consumers. Specifically, the framework developed by Pine and Gilmore (2000) is adopted to look into the effect of product, service and experience qualities on intention to revisit.

The explanatory sequential mixed-methods design was used to articulate the intention of consumers to revisit coffee concept shops. A preliminary study was conducted to define regular and irregular consumers. Self-administered questionnaire was first administered before using interview to elicit more insights and triangulate the findings.

The combination of both quantitative and qualitative findings show that the experiences of regular consumers at coffee concept shops include personal routine activities, while the experiences of irregular customers are composed of occasions with specific and collective purposes. While the intention to revisit of the former is related to the product and service quality, the intention of the latter is largely affected by its service and experience quality.

Given the rapid rise of coffee concept shops in the developing markets, the use of a mixed-methods design provides more insights into the intention to revisit of the regular and irregular consumers. It underscores the importance for the organisations to know what really matters to the diverse consumers.

Purpose – This study aims to design and build a wireless supervisory control and data acquisition (SCADA) system based on Protocol AX.25 with the aim of monitoring the performance of several parameters in Microhydro Power Plant (MHPP). This system can monitor several MHPP parameters such as voltage, current, frequency, and turbine rotation so that it can be accessed directly at one central location.

Design/Methodology/Approach – The design is done by taking into account the real parameters that exist in the MHPP. Some parameters that become the main object to see the performance of MHPP are voltage, current, frequency, and turbine rotation. The voltage generated by the MHPP must be adjusted to the voltage supplied by State Electricity Company to the consumer, including the phase used. The resulting stream should also be monitored for power to be adjusted to the turbine spin. The generator frequency is kept stable according to the standard frequency of the State Electricity Company generator.

Findings – The remote terminal unit (RTU) system has been simulated using 2 ACS712 current sensors, voltage sensor, zero crossing point, frequency sensor, and rotation sensor functionalized to monitor MHPP parameters. The AX.25 protocol has been applicable in the wireless SCADA network for monitoring the performance of MHPP by embedding in KYL-1020UA transceiver radio using the 433 MHz frequency and the audio frequency shift keying modulation system. Radio transmitter KYL-1020UA has been successfully simulated to send data from sensors to display on the computer through SCADA built applications. The data changes in the RTU section can be displayed properly on the graphic user interface in accordance with the existing display at the MHPP location.

Research Limitations/Implications – There are only two RTUs that will be connected to communicate, in this case MHPP-1 with callsign “RTU-001” and MHPP-2 with callsign “RTU-002.” While the existing devices in the data access section parameters MHPP as master station with callsign “MSSCADA” monitoring the performance of parameters sent from the RTU. There is no collision or error in data transmission. Baudrate is varied at 1,200 bps, 2,400 bps, 4,800 bps, and 9,600 bps for effective throughput calculation and AX.25 protocol efficiency. The transmission distance is varied at 100 m, 200 m, 300 m, and 500 m to see the bit error rate with baudrate 1,200 bps and 9,600 bps.

Practical Implications – This product is expected to be applied to several MHPP locations in Aceh Province so that its monitoring system is more centralized and efficient.

Originality/Value – This research if for the efficient monitoring of several MHPP located far apart and can be monitored in one central location so that operators do not have to be located at the plant site.

Purpose – The purpose of this research is to design and build a wild animal pest repellent device with combination of passive infrared (PIR) sensor and ultrasonic signal based on microcontroller as system controller. The PIR sensor is used to detect the presence of wild animal objects and ultrasonic signals to interfere with the hearing.

Design/Methodology/Approach – The design of the system is built based on microcontroller as the system controller. The system as a whole includes hardware and software. The design of hardware consists of the system design on the transmitter side and the system design on the receiver side, while the software in the of system are algorithms using C language programming.

Findings – The resulting repellent device can detect animals approaching up to a distance of 5 m and may interfere with its hearing with a 40 kHz ultrasonic frequency up to a distance of 20 m. The system also uses remote monitoring devices using 433 MHz radio frequency up to a distance of 60 m.

Research Limitations/Implications – Each animal has different hearing frequencies, as well as some wild animals, but the hearing frequencies of wild animals are generally at ultrasonic frequencies. The frequency of animal hearing may vary from audio frequency to ultrasonic frequency, so ultrasonic wave emission testing with varying frequencies is required.

Practical Implications – This research combines systems on transmitters and receivers, with real-time monitoring of wild animal positions, and it can be possible to monitor the position of more detailed animals by installing more types of sensors as well as increasing the number of sensors.

Originality/Value – This paper may provide additional insight into the hearing frequencies of animals and may also serve as comparable papers for similar studies.

The purpose of this paper is to present the high-frequency performance of 0.13-μm n-type metal-oxide-semiconductor (NMOS) transistors with various multi-finger configurations for implementation in millimeter-wave (mm-wave) frequency.

A folded-like double-gate transistor layout is designed to enable the transistor to work in the mm-wave region. Different sizes of transistors with variation in finger width (W_F ) and number of fingers (N_F ) were fabricated to determine the optimum size of the transistor. The extrinsic parasitic elements of selected transistors were extracted and investigated. The radio frequency (RF) performance of these samples were then analyzed and compared.

The proposed layout performed well with the highest maximum oscillation frequency (f_max ) achieved at 122 GHz. Based on the comparison done, the optimum W_F obtained for the layout is at 2.0 μm. It is found that the extrinsic parasitic capacitance is more dominant than the parasitic resistance in affecting the f_max . In s-parameter analysis, it is observed that the transistor with the least N_F has smaller variance in small-signal gain throughout the measurement frequency. The maximum stable gain for the samples is also found to be roughly similar and independent of N_F .

A new layout structure for an NMOS transistor that works in mm-wave frequency is proposed. Experimental analyses presented here cover for both N_F and W_F , unlike others which focus on either N_F or W_F only.

This paper aims to provide feasible business model options that benefit all stakeholders; the government, the investor and especially the inhabitants in Maluku and Papua, the less-favored business regions in Indonesia.

Three feasible business model options result from ICT for development literature, current role of the government, other models and investment scheme review, statistical analysis, technology analysis and investment simulations.

This paper proposes three different feasible business model options. The infrastructure subsidy model, which combines 20 per cent private investment and 80 per cent government subsidy, is the most feasible business model based on investment simulations. This model which combines 20 per cent private investment and 80 per cent government subsidy provides stronger determination of Indonesian Government for serving rural and remote people. The revenue subsidy and the mixed project subsidy are alternative models that may provide more attractive schemes from the standpoint of investors.

However, current paper has limitation which is subject to enhance for better analysis in future research such as implementation of the in-depth assessment of risk management system to deal with all exposed risks.

This paper provides that setting up a complete telecommunication access infrastructures in eastern Indonesia is feasible under new proposed models.

The new proposed models provide stronger determination of Indonesian Government for serving rural and remote people and minimizing the digital divide in eastern area.

Under the new proposed models, the role and capacity of the government is adjusted. The government should dominate and be less dependent on private investment. Also, the government should shift from triggering service penetration into developing a complete infrastructure set up.

The proliferation of the coronavirus disease (COVID-19) has threatened the service industry, especially the restaurant sector, requiring innovative ways to help restaurants overcome this challenge. Thus, based on the stimulus–organism–response (SOR) model, the purpose of this study is to examine the role of customers' perception of a restaurant's innovativeness (CPRI) in brand evangelism by mediating customer engagement (CE). Additionally, this study examines the moderating role of customer openness to experience.

A Web-based survey collected the primary data from 483 Egyptian customers. The data were analysed using the partial least squares structural equation modelling method based on WarpPLS.7 software.

According to the findings, CPRI, which acts as a stimulus in the SOR model, positively affects CE (organism) and brand evangelism (response). CE positively affects restaurant evangelism. Additionally, CE mediates the relationship between CPRI and evangelism. Openness to experience moderates the relationship between CPRI, engagement and brand evangelism.

This study addresses the gaps in understanding CE and brand evangelism within the context of restaurant innovation. This study assesses restaurant innovativeness scales of developing economies in multiple dimensions. Egyptian restaurant marketing managers should innovate products, services, experiences, and promotions to increase consumer engagement and feedback through technology.

This study investigates how Egyptian restaurants engage with and evangelise customers through innovation. This is one of the few studies that examine brand evangelism in a restaurant setting from the perspective of the SOR theory. Additionally, this study analyses CE as a mediator and openness to experience as a moderator.

–The purpose of this paper is to determine strategies in controlling over the function of paddy field in Central Java.

Purposive sampling was employed by having 12 people interviewed. Analytical hierarchy process was used to determine a strategy related to policy control toward agricultural land conversion.

The results indicated priorities which are recommended to include in the policy toward the function of the land conversion in Central Java. They are: first, the application of laws that regulate land conversion mechanism; second, tightening or restricting and prohibiting rules for anyone who wants to change the function of agricultural land; and finally, zoning or clustering region based on urban spatial and land use.

This study suggests that the government is expected to invest directly for agriculture and plantation by avoiding the use of existing rice field.

It is also advisable for government to utilize the available unused land.

This paper captures factual condition of the decrease of the land use for agriculture which has been very critical issues in any agrarian countries. This is essential to know the core of the problem and possible solutions for similar case in other typical nations.