Armendariz, Marcelino (2010-12). Tunable Substrate Integrated Waveguide Filters Implemented with PIN Diodes and RF MEMS Switches. Master's Thesis. Thesis uri icon

abstract

  • This thesis presents the first fully tunable substrate integrated waveguide (SIW) filter implemented with PIN diodes and RF MEMS switches. The methodology for tuning SIW filters is explained in detail and is used to create three separate designs. Each SIW cavity is tuned by perturbing via posts connecting or disconnecting to/from the cavity's top metal layer. In order to separate the biasing network from the SIW filter, a three-layer PCB is fabricated using Rogers RT/duroid substrates. The first tunable design utilizes the Philips BAP55L PIN diode. This two-pole filter provides six frequency states ranging from 1.55 GHz to 2.0 GHz. Fractional bandwidth ranges from 2.3 percent - 3.0 percent with insertion loss and return loss better than 5.4 dB and 14 dB respectively for all frequency tuning states. The second tunable design utilizes the Radant RMSW-100 MEMS switch, providing six states ranging from 1.65 GHz to 2.1 GHz. Fractional bandwidth for this filter varies from 2.5 percent - 3.0 percent with insertion loss and return loss better than 12.4 dB and 16 dB respectively for all states. The third design utilizes the OMRON 2SMES-01 RF MEMS relay, providing fourteen states ranging from 1.19 GHz to 1.58 GHz. Fractional bandwidth ranges from 3.6 percent - 4.4 percent with insertion loss and return loss better than 4.1 dB and 15 dB respectively for all frequency states. Two of the three designs (Philips PIN diode and OMRON MEMS) produced good results validating the new SIW filter tuning methodology. Finally, to illustrate the advantage of microstrip planar structures integrated with SIW structures, low pass filters (LPFs) are implemented along the input and output microstrip-to-SIW transition regions of the tunable SIW filter. With minimal change to the overall filter size, this provides spurious suppression for the additional resonant modes inherently present in waveguide structures. The implemented design utilizes the same OMRON MEMS tunable SIW filter specifications. This two-pole tunable filter provides the same performance as the previous OMRON MEMS design with exception to an added 0.7 dB insertion loss and spurious suppression of -28 dB up to 4.0 GHz for all frequency tuning states.
  • This thesis presents the first fully tunable substrate integrated waveguide (SIW)
    filter implemented with PIN diodes and RF MEMS switches. The methodology for
    tuning SIW filters is explained in detail and is used to create three separate designs.
    Each SIW cavity is tuned by perturbing via posts connecting or disconnecting to/from
    the cavity's top metal layer. In order to separate the biasing network from the SIW filter,
    a three-layer PCB is fabricated using Rogers RT/duroid substrates. The first tunable
    design utilizes the Philips BAP55L PIN diode. This two-pole filter provides six
    frequency states ranging from 1.55 GHz to 2.0 GHz. Fractional bandwidth ranges from
    2.3 percent - 3.0 percent with insertion loss and return loss better than 5.4 dB and 14 dB
    respectively for all frequency tuning states. The second tunable design utilizes the
    Radant RMSW-100 MEMS switch, providing six states ranging from 1.65 GHz to
    2.1 GHz. Fractional bandwidth for this filter varies from 2.5 percent - 3.0 percent with insertion loss
    and return loss better than 12.4 dB and 16 dB respectively for all states. The third design
    utilizes the OMRON 2SMES-01 RF MEMS relay, providing fourteen states ranging
    from 1.19 GHz to 1.58 GHz. Fractional bandwidth ranges from 3.6 percent - 4.4 percent with insertion loss and return loss better than 4.1 dB and 15 dB respectively for all frequency
    states. Two of the three designs (Philips PIN diode and OMRON MEMS) produced
    good results validating the new SIW filter tuning methodology.
    Finally, to illustrate the advantage of microstrip planar structures integrated with
    SIW structures, low pass filters (LPFs) are implemented along the input and output
    microstrip-to-SIW transition regions of the tunable SIW filter. With minimal change to
    the overall filter size, this provides spurious suppression for the additional resonant
    modes inherently present in waveguide structures. The implemented design utilizes the
    same OMRON MEMS tunable SIW filter specifications. This two-pole tunable filter
    provides the same performance as the previous OMRON MEMS design with exception
    to an added 0.7 dB insertion loss and spurious suppression of -28 dB up to 4.0 GHz for
    all frequency tuning states.

publication date

  • December 2010