M. Rajashekharaiah

Washington State University, Pullman, WA, United States

Are you M. Rajashekharaiah?

Claim your profile

Publications (14)0 Total impact

  • Source
    M. Rajashekharaiah, P. Upadhyaya, Deukhyoun Heo
    [Show abstract] [Hide abstract]
    ABSTRACT: An enhanced linearity improvement technique based on the third order intermodulation distortion cancellation or gm3 cancellation technique is presented in this paper. By identifying the issues related to the conventional gm3 cancellation method, the proposed technique is used to design a 0.18mum CMOS LNA using Jazz semiconductor's BiCMOS process. With an IIP3 of more than +16dBm and gain of more than 15dB, the enhanced linearity LNA or EL2NA with a current consumption of 9mA from a 1.8V supply, provides an efficient way of improving linearity of 5G range direct conversion receivers
    Circuits and Systems, 2006. ISCAS 2006. Proceedings. 2006 IEEE International Symposium on; 06/2006
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A 5.7 GHz fully integrated complementary LC voltage controlled oscillator (CLC VCO) has been designed in an inexpensive 0.25-μm digital CMOS process for low power neurosensory application. Consuming only 2mA of current from a 2.5 V power supply, the CLC VCO achieves a measured single-sideband phase noise of -92.75 dBc/Hz and -97.6 dBc/Hz at 600 KHz and 1.0 MHz offset frequency, respectively. The CLC VCO is able to output -5dBm of power at the single-ended output to a 50-Ohm load to meet demands of high-date rate short reach on-off keying (OOK) wireless transmission. Various low power techniques used to improve phase noise in the LC VCO are also discussed.
    Microwave Symposium Digest, 2005 IEEE MTT-S International; 07/2005
  • P. Upadhyaya, M. Rajashekharaiah, Deukhyoun Heo, Y.-J.E. Chen
    [Show abstract] [Hide abstract]
    ABSTRACT: This paper presents a new low power and high IIP2 0.25- μm CMOS doubly balanced sub-harmonic mixer for a 5 GHz Industrial Scientific Medical (ISM) band direct conversion-zero IF receiver. Using a 1/2×LO frequency generation scheme, the sub-harmonic mixer, designed and fabricated, overcomes the LO self-mixing problem common in conventional direct conversion receivers (DCR). Measurements show the sub-harmonic mixer is able to achieve voltage conversion gain of 8.2 dB, input compression, P<sub>1dB</sub> of -8 dBm and IIP<sub>3</sub> of -2.5 dBm while consuming only 1.35 mA of DC current. Measured results correlate well with simulated results where with 1% g<sub>m</sub> mismatch, 0.5 % load mismatch and 2° LO phase error, the mixer is able to achieve high IIP<sub>2</sub> of 55.3 dBm, IIP<sub>3</sub> of -6.5 dBm, and voltage conversion gain of 8 dB. The proposed mixer takes up less than 1 mm<sup>2</sup> of silicon real estate, including test die pads.
    Radio Frequency integrated Circuits (RFIC) Symposium, 2005. Digest of Papers. 2005 IEEE; 07/2005
  • M. Rajashekharaiah, P. Upadhyaya, Deukhyoun Heo, E. Chen
    [Show abstract] [Hide abstract]
    ABSTRACT: An on-chip active balun with gain and phase mismatch within 0.5 dB and 1 degree, respectively, integrated with a gain controllability feature, is presented. Applicable for direct conversion receiver circuits, the balun has been designed to operate in the 5-6 GHz range with a bandwidth of 400 MHz. With an output P1dB of -14.4 dBm, it is capable of being used as an independent amplifier in addition to acting as an active balun.
    Circuits and Systems, 2005. ISCAS 2005. IEEE International Symposium on; 06/2005
  • [Show abstract] [Hide abstract]
    ABSTRACT: A high isolation 15-GHz radiation tolerant SPDT (single-pole double-throw) annular MOSFET switch, for space application, was designed and integrated in a SiGe BiCMOS process. Schwartz-Christoffel transformation, based on conformal mapping, and parasitic capacitance extraction methods were utilized to derive the equivalent circuit model of the octagonal annular MOSFET, which has demonstrated improved total dose radiation tolerance in CMOS circuits. The designed switch achieves 40.5-dB isolation at 15-GHz
    Microelectronics and Electron Devices, 2005. WMED '05. 2005 IEEE Workshop on; 05/2005
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A 5.7 GHz fully integrated complementary LC voltage controlled oscillator (CLC VCO) has been designed in an inexpensive 0.25-μm digital CMOS process targeting low power short reach 100 Mbs on-off keying wireless transmitter (OOK) for neurosensory application. Consuming only 2 mA of current from a 2.5 V power supply, the CLC VCO achieves a measured single-sideband phase noise of -92.75 dBc/Hz and -97.6 dBc/Hz at 600 KHz and 1.0 MHz offset frequency, respectively. The CLC VCO is able to output -5 dBm of power at the single-ended output to a 50 ohm load to meet demands of high-data rate short reach on-off keying wireless transmission. Various low power techniques used to improve phase noise in the LC VCO are also discussed.
    SoutheastCon, 2005. Proceedings. IEEE; 05/2005
  • M. Rajashekharaiah, P. Upadhyaya, Deukhyoun Heo, E. Chen
    [Show abstract] [Hide abstract]
    ABSTRACT: An on-chip active balun with good gain and phase mismatch performance of within 0.5 dB and 1 degree, respectively, is presented in this paper. Applicable for direct conversion receiver circuits, the presented balun features reconfigurability in the form of controllable gain, designed to operate in the 5-6 GHz range with a bandwidth of 400 MHz. With good linearity, input/output matching and gain and with improvement in noise performance, the proposed active balun circuit could effectively be used as the first stage of an RF front end replacing the LNA.
    SoutheastCon, 2005. Proceedings. IEEE; 05/2005
  • Deukhyoun Heo, Parag Upadhyaya, Mallesh Rajashekharaiah
    Encyclopedia of RF and Microwave Engineering, 04/2005; , ISBN: 9780471654506
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Not Available
    Microelectronics and Electron Devices, 2005. WMED '05. 2005 IEEE Workshop on; 02/2005
  • [Show abstract] [Hide abstract]
    ABSTRACT: A low noise amplifier (LNA) with a new gain controllable on-chip active balun has been designed for a 5 GHz industrial scientific medical (ISM) band direct conversion receiver (DCR). The active balun provides good gain and phase matching with LNA gains of 19.5 dB and 12 dB in high gain and low gain modes, respectively, while achieving a noise figure of 3 dB and an IIP<sub>3</sub> of -11.5 dBm. In the low gain mode the LNA provides 50% power savings by using 15mW from a 3V supply.
    Solid-State and Integrated Circuits Technology, 2004. Proceedings. 7th International Conference on; 11/2004
  • [Show abstract] [Hide abstract]
    ABSTRACT: A new low power doubly balanced sub-harmonic mixer for 5-GHz industrial scientific medical (ISM) band direct conversion - zero IF receiver in an inexpensive 0.25-μm CMOS is presented. The mixer uses a power and silicon real estate efficient LO frequency generation scheme to overcome LO self-mixing problem common in conventional direct conversion receivers (DCR). Simulated with 1% gm mismatch, 0.5% load mismatch and 2° LO phase error, the mixer is able to achieve very good IIP<sub>2</sub> of 55.3 dBm, IIP<sub>3</sub> of -6.5 dBm, and voltage conversion gain of 8 dB while consuming less than 1.75 mA from a single 3V supply. The mixer also achieves input compression, P<sub>1dB</sub> of -12 dBm and an overall double side band noise figure of 5.96 dB. Including die pads, the proposed mixer takes up less than 1mm<sup>2</sup> of silicon real estate.
    Solid-State and Integrated Circuits Technology, 2004. Proceedings. 7th International Conference on; 11/2004
  • P. Upadhyaya, M. Rajashekharaiah, Deukhyoun Heo
    [Show abstract] [Hide abstract]
    ABSTRACT: A new low power 5.6 GHz doubly balanced sub-harmonic mixer for industrial scientific medical (ISM) band direct conversion - zero IF receiver in 0.25-μm CMOS is presented. The mixer uses a power efficient LO frequency generation scheme to overcome the LO self-mixing problems common in conventional direct conversion receivers (DCR). Simulated with 1% gm mismatch, 0.5% load mismatch and 2° LO phase error, the mixer is able to achieve 55 dBm of IIP2, -6.5 dBm of IIP3 and voltage conversion gain of 8 dB while consuming less than 1.75 mA from a single 3 V supply. The mixer also achieves input compression of -12 dBm and an overall double side band noise figure of 5.96 dB. The proposed mixer takes up less than 1 mm<sup>2</sup> of silicon real estate.
    Microelectronics and Electron Devices, 2004 IEEE Workshop on; 02/2004
  • M. Rajashekharaiah, P. Upadhyaya, Deukhyoun Heo
    [Show abstract] [Hide abstract]
    ABSTRACT: A dual gain low noise amplifier for a 5.6 GHz ISM band direct conversion receiver, has been designed using a TSMC 0.25 μm CMOS process and features a gain controllable on-chip active balun. The LNA provides gains of 19.5 dB and 12 dB in the two modes with 50% power savings in the low gain mode, while a noise figure of 3.1 dB and an IIP3 of -11.5 dBm have been achieved. A simple and novel gain control technique has been adopted and the gain control circuitry has been integrated with the balun.
    Microelectronics and Electron Devices, 2004 IEEE Workshop on; 02/2004
  • Source
    MALLESH RAJASHEKHARAIAH