• 作者： S.K. SANYAL; R. NANDI
• 作者服務機構： 印度加爾各答Jadavpur University電子及電信工程學系
• 中文摘要： 　　本文提出一個雙運算放大器，雙電阻的弦波振盪器電路結構一其創新性在於使用最少數目的元件、頻率可調，雙運算放大器可同時輸出兩相的弦波波形，和極簡易的電路結構。而利用運算放大器的雙極點模型所預測的頻率可調範圍已經實驗證明。本文也提出由互補金氧半（CMOS）開關連接電阻達成預設頻率點的數位控制技術。此振盪器所產生頻率點的控制和掃描由一個使用Intel 8085微處理器的SDA-UNI-01電腦系統達成。它更可被用於連續相位頻移調變（CPFSK）和相移調變（PSK）波形產生器的設計，藉由電阻和開關及雙通道的分工可實現上述電路，而開關的驅動碼則由微處理器產生。
• 英文摘要： A simple two-Operational Amplifier (OA) two-resistor active-R sinusoid oscillator configuration isproposed. The novelties of the configuration are the use of only the minimum number of active/passivecomponents, frequency -tunability by a single grounded resistor at low sensitivities, availabilityof quadrature oscillations at the two OA outputs and extreme simplicity of the circuit structure suitablefor microcircuit adaptation. Analysis based on the OA-double pole model predicts a wide range ofcontinuous -tunability which has been verified experimentally. A novel technique of digital control ofat certain preselected spot frequencies by use of an array of grounded binary weighted switchedresistors employing CMOS switches has been described. The control and sweeping of the spot frequenciesgenerated by the active-R oscillator were done by a SDA-UNI-01 microcomputer system based on theIntel 8085 microprocessor. Further application of the oscillator towards the design of a continuous phaseFSK (CPFSK) and PSK wave generator by appropriate resistor switching and switched multiplexing of thequadrature channels, respectively, has been examined wherein the switch driving codes were derived fromthe microprocessor.
• 中文關鍵字： signal processing; microprocessor applicationl digital modulation
• 英文關鍵字： --