A. Bavisi

A multiple frequency signal generator for 802.11a/b/g VoWLAN type applications using organic packaging technology

This paper proposes a signal generator that simultaneously generates multiple frequencies while using the same set of passive components. The first example demonstrates the capability of simultaneously generating 2.45GHz and 5.2 GHz (WLAN a/b/g). Additionally, an oscillator capable of concurrently generating 900 MHz and 1.9 GHz (GSM and DCS-1800 band) is also presented. This paper uses the theory of multi-resonant passives and shows their immediate effects on different topologies of signal generators that generate signals for two or more frequency bands. In addition, measured and simulated results of individual blocks of such a simultaneous signal generator, such as, filters, individual oscillators, and feedback networks, are demonstrated.

Design and fabrication of integrated RF modules in liquid crystalline polymer (LCP) substrates

This paper presents the design and fabrication of fully-packaged RF modules that are suitable for integration in portable handset applications. The system blocks utilize high Q passive devices that are embedded in liquid crystalline polymer (LCP) based substrates. Firstly, the paper introduces the packaging technology that utilizes multiple sheets of LCP substrate. Characterization of high Q inductors on the multi-layer process is then demonstrated showing scalability of inductor size and Q from 900 MHz to 10 GHz. Finally, the paper presents the results of the following key LCP based RF modules: voltage controlled oscillators, concurrent dual-band oscillators, mixers, filters, and baluns. A comparison with the current state-of-the-art is made. The paper shows that the implemented system modules are smaller in size, with superior electrical performance to currently available discrete solutions. The paper shows that the proposed technology supports high-density integration at low cost and hence, is suitable for large volume commercial wireless handheld applications. Finally, a MEMS process to be integrated on the proposed LCP technology for tunability of the modules is presented.

A 802.11a WLAN oscillator with high Q embedded passives on laminate-type organic package

Phase noise, output RF amplitude, and jitter are the oscillator performance characteristics which are determined by the DC power consumed and the quality factor (Q) of the passives. In a multi-standard environment, low phase noise enables achieving high SNR for all standards in the presence of noise and interference. CMOS and similar IC technologies limit the DC voltage supply and provide very low Q inductors and capacitors (/spl sim/6 to 30), trading the oscillators performance with the DC power consumed. The paper presents a low power, low phase noise Colpitts oscillator at 5.2 GHz for WLAN (IEEE 802.11a) application. The adjacent channel interference suppression requirement of the 802.11a WLAN system (5.15-5.35 GHz, 5.725-5.825 GHz) is approximately 25 dB with an SNR of 19 dB for a BER of 10/sup -6/ in a 64 QAM system. This leads to a phase noise requirement of at least -110 dBc/Hz at 1 MHz offset (Bhattacharjee, J. et al., 2002 IEEE MTT-S Int. Microwave Symp. Dig., vol.1, p.585-8, 2002).

Design of a dual frequency oscillator for simultaneous multi-band radio communication on a multi-layer liquid crystalline polymer substrate

This paper presents the design of a dual frequency oscillator that simultaneously generates two signals of different frequencies. The dual frequency oscillator was implemented in a novel multi-layer laminate-type process technology that uses multiple layers of liquid crystalline polymer (LCP) substrate. The oscillator core employs one lumped-element second-order resonator and one lumped-element fourth-order resonator to generate 1.79 GHz and 900 MHz synchronous signals. The silicon-bipolar based dual frequency oscillator utilizes the broad-band nature of the Qs of the passives in LCP to generate signals that are spaced at least one octave away from each other

Chip-package codesign of integrated voltage-controlled oscillator in LCP substrate

This paper presents the design and characterization of a negative resistance type 1.9-GHz oscillator using high quality factor (Q) embedded lumped-element LC passives in an organic-based substrate with liquid crystalline polymer (LCP) dielectric material. A design strategy using analytical models is implemented to determine the value of the base inductance subject to the constraints set by power dissipation. Additionally, the effect of component Qs on the phase noise is qualitatively discussed. This paper also addresses the effects of the parasitics of the surface-mount active devices on the noise spectrum of a negative resistance type voltage-controlled oscillator (VCO). The designed VCO is fully embedded in the LCP substrate and uses high Q on-package passive components. The VCO was measured to operate at 1.92 GHz dissipating 14 mW of dc power and measured a phase noise of -118dBc/Hz and -133 dBc/Hz at 600 KHz and 3-MHz offset, respectively. The high Q of the LC tank circuit was utilized to optimize the VCO to operate from a 2-V supply at bias current of 0.9 mA. Finally, the design and implementation issues in a 2.25-GHz Colpitts oscillator on LCP substrate are shown. The effects of scaling capacitance ratio on VCO phase noise and on power consumption are verified for the Colpitts oscillator

Design and applications of high Q passive devices on multilayered liquid crystalline polymer based substrates for handset applications

In the recent past, fully packaged RF modules suitable for integration in wireless handsets have been fabricated on organic packaging technology that uses a single sheet liquid crystalline polymer (LCP) substrate. This paper demonstrates the RF characterization of inductors that were fabricated on two different stack-ups utilizing different configurations of the LCP substrate. The paper, then, shows the implementations of the embedded LC passives in RF front-end modules such as voltage controlled oscillators (VCOs) and tunable filters. The first application is the design and implementation of a 1.8 GHz feedback oscillator in a novel multilayer laminate-type process technology that uses three layers of LCP substrate. The microstrip type oscillator measures a phase noise of -117 dBc/Hz at 100 KHz offset at 10 mW of power consumption. The oscillator meets the stringent phase noise specifications of cellular systems for both mobile-station and base-stations. The final application of the high quality factor (Q) passives is in the design and implementation of voltage tunable filters useful for WLAN applications. The filters were fabricated on a completely different stack-up that uses two layers of LCP substrate. The filter prototype is tunable from 1.75 to 2.03 GHz with an insertion loss of 2.5 dB using lossy surface-mount varactor diodes.

A 9 GHz, 5 mW VCO using lumped-element transformer feedback in 150 GHz f/sub T/ SiGe HBT technology

This paper presents the design of a novel SiGe HBT voltage controlled oscillator (VCO) that uses a lumped-element transformer as the feedback network. The VCO design employs a filter-type transformer, as opposed to an inductive transformer, to improve both the power consumption and tuning range. Unlike for the conventional cross-coupled differential oscillator and the coupled-Colpitts oscillator, the transformer isolates the frequency selecting passive components from the parasitics of the biasing circuitry, enabling a linear tuning range of over 1 GHz (12 %) at 10 GHz. The isolation also improves the resonator loaded Q, thereby reducing the power consumption of the VCO. The measured phase noise varied between -108 dBc/Hz to -104 dBc/Hz @ 1 MHz offset over the entire tuning range of 1.04 GHz. The oscillator provides an output power of -7.5 dBm without any buffering, at 4.75 mW of power consumption from a 2 V power supply

Design of a system-in-package based low phase noise VCO using 3-D integrated passives on a multilayer liquid crystalline polymer substrate

This paper presents the design of a transformer based LC oscillator in a novel multilayer laminate-type process technology that uses multiple layers of liquid crystalline polymer (LCP) dielectric material. The VCO core employs a lumped-element transformer as the resonator to achieve low phase noise at low power consumption. The VCO is designed at 1.9 GHz and measures a phase noise of -116 dBc/Hz @ 100 KHz offset from the carrier at 12 mW of DC power consumption, inclusive of the output buffer. The paper uses a comparative experimental approach to determine the key passive elements of the resonator that significantly contribute to the VCO phase noise. To verify the approach, two identical Si bipolar VCOs with resonators of different group delay were fabricated on a novel six metal layer LCP process with each VCO occupying an area of 5.3 /spl times/ 5.8 mm/sub 2/ (including RF output and supply pads). This paper experimentally verifies that the parasitic EM coupling between the resonator components at frequencies well beyond the third harmonic causes the VCO frequency to shift to the frequency of coupling. A full-wave EM solver and a macro-modeling tool were used to develop a broad-bandwidth circuit model (/spl sim/ 10 GHz) of the resonator. This model was used in circuit simulations to analyze and eliminate the spurious oscillatory behavior of the VCO due to the EM coupling between the resonator elements.