Design of DMB Nonuniform BPF Using LTCC

Recently, RF systems have rapidly grown with the extension of the mobile communication service. The mobile service companies are providing the satellite broadcasting and common usage are expected. Coinciding with current trend, the development of improved satellite DMB (Digital Multimedia Broadcasting) tuner is required. To improve the receiving sensitivity under the poor communication circumstance, it is necessary to design the LNA (Low Noise Amplifier) with outstanding low noise characteristic and the BPF (Bandpass Filter) to transmit only desired signal without distortion and loss. Besides high reliability, the miniaturization and lightweight are required for design of mobile terminals. In this paper, we designed and fabricated DMB nonuniform SIR-type BPF with embedded tunable pads, which operates at 2642 MHz and is embedded in the substrate of RF module of a tuner with LTCC. As a result, we obtained the passband insertion loss of 2.4 dB and the passband ripple of 0.08 dB. So this BPF is applicable to RF module of a satellite DMB tuner.