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"The book discusses active devices and circuits for microwave communications. It begins with the basics of device physics and then explores the design of microwave communication systems including analysis and the implementation of different circuits. In addition to classic topics in microwave active devices, such as p-i-n diodes, Schottky diodes, step recovery diodes, BJT, HBT, MESFET, HFET, and various microwave circuits like switch, phase shifter, attenuator, detector, amplifier, multiplier and mixer, the book also covers modern areas such as Class-F power amplifiers, direct frequency modulators, linearizers, and equalizers. Most of the examples are based on practical devices available in commercial markets and the circuits presented are operational. The book uses analytical methods to derive values of circuit components without the need for any circuit design tools, in order to explain the theory of the circuits. All the given analytical expressions are also cross verified using commercially available microwave circuit design tools, and each chapter includes relevant diagrams and solved problems. It is intended for scholars in the field of electronics and communication engineering."

"This textbook provides an in-depth treatment of the physics of power semiconductor devices that are commonly used by the power electronics industry. Drawing upon decades of industry and teaching experience and using numerous examples and illustrative applications, the author discusses in detail the various device performance attributes that allow practicing engineers to develop energy-efficient products. Coverage includes all types of power rectifiers and transistors and analytical models for explaining the operation of all power semiconductor devices are developed and demonstrated in each section of the book. Throughout the book, emphasis is placed on deriving simple analytical expressions that describe the underlying physics and enable representation of the device electrical characteristics. This treatment is invaluable for teaching a course on power devices because it allows the operating principles and concepts to be conveyed with quantitative analysis. The treatment focuses on silicon devices but includes the unique attributes and design requirements for emerging silicon carbide devices. This new edition also includes a chapter on the impact of power semiconductor devices on energy savings and reduction of carbon emissions."

"Pengaruh doping potassium (K) pada lanthanum manganite La1-xKxMnO3 (x= 0; 0,1; 0,2; 0,3) terhadap sifat penyerapan gelombang mikro telah selesai dipelajari. Sampel disintesis menggunakan metode Sol-Gel dengan suhu kalsinasi 600˚C selama 6 jam dan suhu sintering 750˚C selama 24 jam. Hasil analisis XRD menunjukkan bahwa seluruh sampel memiliki struktur kristal rhombohedral dengan space group R-3c. Ukuran kristalit sampel berdasarkan uji SEM-EDS berkisar antara 80 – 400 nm. Hasil karakterisasi EDS menunjukkan sinar-x karakteristik masing-masing komponen timbul pada hasil EDS. Karakterisasi sifat magnetik menggunakan VSM menunjukkan bahwa sifat magnetik sampel mengalami transisi dari paramagnetik pada sampel menjadi ferromagnetik seiring dengan bertambahnya komposisi potassium. Uji VNA dilakukan pada frekuensi x-band, yakni pada rentang frekuensi 8 – 12.5 GHz. Nilai reflection loss masing-masing sampel adalah -4,58 dB untuk sampel LKMO-0; -5,47 dB untuk LKMO-1; -4,65 dB untuk LKMO-2, dan -5,19 dB untuk LKMO-3. Puncak reflection loss seluruh sampel rata-rata berada pada frekuensi 9 GHz. Pada frekuensi tersebut juga sampel LKMO-1 memiliki nilai permeabilitas real dan imajiner yang paling tinggi daripada sampel lainnya.

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The effect of potassium (K) doping on lanthanum manganite La1-xKxMnO3 (x= 0; 0.1; 0.2; 0.3) on the microwave absorption properties has been studied. The samples were synthesized using Sol-Gel method with a calcination temperature 600˚ for 6 hours and sintering temperature 750˚ for 24 hours. The XRD result showed that all of the samples are rhombohedral with space group R-3c. The crystallite size of the samples based on the SEM-EDS test ranges from 80-400 nm and characteristic x-rays of each component appear in the EDS results. Magnetic characterization using VSM revealed that the magnetic properties of the samples changed from paramagnetic to ferromagnetic as the potassium composition increased. VNA characterization was conducted at the x-band frequency with range 8-12.5 GHz. The reflection loss values of each sample were -4.58 dB for LKMO-0 sample; -5.47 dB for LKMO-1; -4.65 dB for LKMO-2, and -5.19 dB for LKMO-3. The peak of reflection loss curve of all samples was averagely at 9 GHz frequencies. At this frequency, the LKMO-1 sample has the highest real and imaginary permeability values compared to the others."