Ki Chan Eun

60-GHz System-on-Package Transmitter Integrating Sub-Harmonic Frequency Amplitude Shift-Keying Modulator

This paper proposes a simple low-temperature co-fired ceramic (LTCC) integrated transmitter using sub-harmonic amplitude shift-keying modulation for 60-GHz wireless communications applications. The transmitter system-on-package (SoP) has been monolithically implemented with a six-layer LTCC block embedding a resonator, modulator, and antenna and two active circuits, including a negative resistance generator and frequency doubler on the block. The transmitter SoP integrating whole millimeter-wave circuitry is as small as 26 times 18 times 0.6 mm3, which needs external interfaces only for supplying dc power and digital input signal. The fabricated transmitter SoP reveals a bit error rate of 10-11 and good eye pattern through a 2.5-m transmission of 800-Mb/s data.

60GHz Rotman lens and new compact low loss delay line using LTCC technology

In this work, the first μ-strip 60GHz Rotman lens and new compact low loss strip delay line using low temperature co-fired ceramic(LTCC) are proposed. The lens has 3 steering capability for +26°, −26°, 0.1° angle, − 10.86dB of side lobe level(SLL), and 28° of half power beam width (HPBW). The Rotman lens is designed in μ-strip structure for integration capability with the system on package(SoP). In order to replace bulky and lossy meander line of the Rotman lens, new compact low loss delay line is developed and verified. It shows remarkable performance; it has smaller insertion loss. Furthermore, It shows 78% of length reduction than meander line. Also, owing to its simple and symmetrical structure, the delay line is reciprocal and analogous.

A Novel GCPW to Rectangular Waveguide Transition for 60 GHz Applications

A new type of grounded coplanar waveguide (GCPW) to rectangular waveguide transition in an LTCC multi-layer structure for 60 GHz applications is proposed in this letter. The GCPW and rectangular waveguide are fully integrated on the same substrate, and the ground wall of the rectangular waveguide is made up of a staggered via fence. The transition is accomplished by inserting a bent short stub. We analyze and prove the novel transition structure by applying an equivalent circuit model. Measured results for a single transition show that the insertion loss is 0.345 dB at 59 GHz and the bandwidth is 6.3 GHz. The proposed transition structure with very low loss at a large bandwidth is very suitable for a SiP of 60 GHz WPAN applications.

High- Q Circular LTCC Resonator Using Zigzagged Via Posts and a

This paper presents two high-Q circular resonators utilizing low temperature co-fired ceramic (LTCC) multilayer circuits for millimeter-wave system-on-package applications. A resonator including zigzagged dual-row via posts for tightly confining electromagnetic energy as a metallic boundary wall will be presented. Another resonator containing the zigzagged dual-row via posts and a lambda/4 short stub on a feeding via post in the circular resonator is used for transmitting energy in the resonator to output load without losses. Simple theories for obtaining high-Q factors using zigzagged dual-row via posts and the feeding technique with the lambda /4 short stub are derived. A total of four layers are used to construct the resonator with a height of 300 mu m (three layers); an additional layer is used for the probe excitation and signal feeding line. The signal feeding line is employed to connect a negative resistance generator monolithic microwave integrated circuit ((-)R MMIC) that consists of conductor backed coplanar waveguide (CBCPW), which is implemented on a layer. A CPW-type double bond wire connects the resonator and (-)R MMIC. The measurement results show that the first and second resonant modes are TM010 at 29.75 GHz and TE010 at 46.75 GHz, respectively. Although the unloaded Q value of the conventional resonator is 204, the proposed resonator with zigzagged dual-row via posts achieved an unloaded Q value of 249, which is a 22.1% improvement. Further, the new resonator with the lambda/4 short stub and zigzagged dual-row via posts yielded an unloaded Q of 296, an improvement of 45.1% for the first resonant mode. In order to verify the resonator performances, the oscillator integrating the proposed resonator is evaluated. The measured output power and phase noise of the oscillator is 18.8 dBm at 27 GHz and -104.67 dBc/Hz at 1 MHz offset, respectively. It can be implemented easily without requiring additional processes or any degradation of performance and therefore is suitable to implement in high integrated systems for millimeter-wave applications.

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This paper presents effects of a resonator output load line on the performance of an oscillator. To verify the effects, we designed three low temperature co- fired ceramic (LTCC) circular resonators to fabricate three different Ka-band oscillators. The output load line of the resonator connecting a negative resistance generator monolithic microwave integrated circuit ([-]R MMIC) is a conductor backed coplanar waveguide (CBCPW). We propose load lines with a back pad or a lambda/4 short stub to reduce radiation loss at the opposite side of the load lines. The unloaded Q-value of the two proposed resonators is 255 (25% improvement) and 274 (33.4% improvement) respectively, compared to a conventional resonator with a value of 204. While the measured output power and phase noise of an oscillator with a conventional resonator is 5.0dBm and -95.17dBc/Hz at 1MHz offset, the two oscillators using the proposed resonators with a back pad or lambda/4 short stub are measured at 6.34 dBm, -97.33 dBc/Hz, 16.84 dBm, and -101.17 dBc/Hz, respectively, at the same bias condition. We can see that the radiation loss of the output load line exerts a great influence not only on the Q-value of a resonator but also on the output power and phase noise of an oscillator. As the resonators are embedded in the multilayer LTCC block, they are also very suitable for implementing millimeter-wave integrated system applications.

Short Stub for Millimeter-Wave System-on-Package Applications

This paper proposes a low loss and broadband grounded coplanar waveguide (GCPW) to waveguide (WG) transition in a low temperature co-fired ceramic (LTCC) multi-layer structure for 60GHz applications. The GCPW and WG are fully integrated on the same substrate, and the ground wall of the embedded WG is made up of a staggered via fence. A 3λ/4 bent short stub is connected between signal line of GCPW and WG ground wall for effective coupling. The WG dimension is gradually increased for broadband characteristic. Measured results for a single transition show that the insertion loss is 0.775dB at 58.3GHz and the 3-dB bandwidth is 6.8GHz from 53.1GHz to 59.9GHz. The proposed transition structure has been packaged in 60GHz LTCC System-in-Package(SiP) receiver module, and a 60GHz wireless data link at 648Mbps over 3m has been demonstrated.

A system-on-package structure LTCC resonator for a low phase noise and power efficient millimeter-wave oscillation

In this paper, a 60 GHz LTCC SiP with low-power CMOS OOK modulator and demodulator is presented. The 60 GHz modulator is designed in a 90-nm CMOS process. The modulator uses a current reuse technique and only consumes 14.4-mW of DC power in the on-state. The measured data rate is up to 2 Gb/s. The 60 GHz OOK demodulator is designed in a 130nm CMOS process. The demodulator consists of a gain boosting detector and a baseband amplifier, and it recovers up to 5 Gb/s while consuming low DC power of 14.7 mW. The fabricated 60 GHz modulator and demodulator are fully integrated in an LTCC SiP with 1 by 2 patch antenna. With the LTCC SiP, 648 Mb/s wireless video transmission was successfully demonstrated at wireless distance of 20-cm.

A GCPW to waveguide transition in 60GHz LTCC SiP

We have developed a low power demodulator for a 60 GHz receiver using 0.13 um CMOS technology. The demodulator consists of two blocks, which are a detector and a post amplifier. The detector detects and demodulates a received signal by using a square-law-detection technique. In this case, because there is no millimeter wave oscillator for frequency conversion, the receiver block becomes simplified, miniaturized, and a structure for low power consumption. A microstrip line has been used for constructing matching networks. Also, a lambda/4 open stub is used for perfect rejection of a 60 GHz signal between the detector and the post amplifier. The post amplifier is composed of an input and output buffer and a gain stage. The cutoff frequency of the post amplifier is 2 GHz, and it has a flat gain within the bandwidth. Thus, the post amplifier acts like a low pass filter, which causes the demodulator not to need any filters and simplifies the system. The 2 Gbps demodulated amplitude-shift-keying (ASK) signal is obtained when the carrier frequency is 60 GHz. The input return loss is less than 25 dB at the center frequency of 60 GHz; the conversion gain of the demodulator is 7 dB when the input power of a demodulator is -13 dBm. The total power consumption is 21.4 mW. These results indicate that the proposed low power demodulator is suitable for 60GHz portable systems.