Now showing 1 - 3 of 3
  • Publication
    Design and characterization of a 3.5 GHz CMOS power amplifier for low-band 5G applications
    (Taylor and Francis Ltd., 2025) ; ; ;
    Rohana Sapawi
    A 3.5 GHz CMOS power amplifier (PA) designed for 5G applications is presented in this study, utilizing the 0.18 µm RF CMOS process technology. The circuit architecture comprises two stages: the first stage employs a cascode topology with a negative voltage applied to the transistor body technique to achieve sufficient gain and minimize current, thereby reducing power consumption. In the second stage, to ensure high efficiency, a class-E amplifier is being used. Measurement results indicate a power gain (S21) of 17.2 dB, a power-added efficiency (PAE) of 45.6% and a saturated power (Psat) of 8.5 dBm, obtained at 3.5 GHz. These findings validate the suitability of the proposed design at low-band frequency for 5G applications. The chip area for the proposed design is 2.45 mm². The discrepancy between simulation and measurement is due to the parasitic in the layout design.
  • Publication
    Design of a 24.5 GHZ CMOS low noise amplifier using 0.13-µM technology for 6G wireless applications
    (Penerbit UTM Press, 2025-11-11) ;
    Asrulnizam Abd Manaf
    ;
    Nuha A. Rhaffor
    ;
    Ruhaifi Abdullah Zawawi
    The need for high-performance circuit designs is growing as wireless communication technologies continue to advance and support newer generations of wireless applications. Much emphasis has been focused on the possibility of the 24 GHz frequency band in next-generation wireless networks, including 5G and beyond. Designing a low noise amplifier (LNA) operating at 24 GHz presents several challenges. The primary concerns include achieving high gain, low power consumption, low noise figure, and while maintaining good linearity and stability. This paper presents the design, simulation, and layout of a CMOS LNA optimized for operation at 24.5 GHz frequency, targeting 6G and beyond wireless communication applications. The proposed LNA employs three stages with a cascode topology at the first stage and follow by a common source stage at second and third stage. The three stages help to achieve high gain, and the source degeneration inductor at the first stage helps to improve linearity. Extensive simulations were conducted using a 0.13-µm CMOS technology, demonstrating a peak gain of 21 dB and a noise figure of 5.6 dB at 24.5 GHz. The LNA also exhibits good linearity and stability over a wide bandwidth. The performance metrics were validated through simulation and comparison, showcasing the feasibility of the designed LNA for 6G applications. This work contributes to the advancement of CMOS-based radio frequency (RF) front-end designs for next-generation wireless communication systems.
  • Publication
    Design of 3.1-10.6 GHz UWB CMOS Power Amplifier using Cascade Topology
    ( 2023)
    Rohana Sapawi
    ;
    Dayang Halimah Abang Mohamad
    ;
    Kuryati Kipli
    ;
    Kismet Hong Ping
    ;
    Norhuzaimin Julai
    ;
    ;
    Dayang Nur Salmi Dharmiza Awang Salleh
    ;
    Dayang Azra Awang Mat
    ;
    Shamsiah Suhaili
    ;
    Asrani Lit
    Power amplifier is an important component in the wireless communication system. Design of the power amplifier in UWB transceiver is challenging as the signal need to be transmitted over a wide bandwidth. Several criteria need to be fulfilled such as good linearity, good wideband matching, high efficiency and low power consumption. This paper presents the design of a power amplifier with 3.1-10.6 GHz using 0.18 μm CMOS technology for ultra-wide band application. The proposed power amplifier used three cascaded amplifier stages in order to achieve good gain and wide-band width. The results show that the proposed power amplifier design has an average gain of 7.28 dB, an input return loss less than-7.48 dB, an output return loss less than-4.782 dB, and group delay variation of ±151.9 ps is achieved over the entire band. A good input 1dB-compression point of 6.67 dBm and input third order intercept point of 0 dBm is achieved at 5 GHz.
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