Balun

About: Balun is a research topic. Over the lifetime, 5375 publications have been published within this topic receiving 52256 citations. The topic is also known as: Telephone balance unit.

Ultra-wideband planar coupled spiral balun

Abstract: A coupled transmission line balun construction employs two pairs of planar interleaved spiral coils ( 3, 5 & 7, 9 ) formed on an electrically insulating or semi-insulating substrate ( 11 ) defining a planar structure. One coil in each pair is connected in series to define the input transmission line of the balun, with one end ( 8 ) of that transmission line being open circuit. The balun provides an ultra-wide bandwidth characteristic in the frequencies of interest for MMIC devices, is fabricated using the same techniques employed with fabrication of MMIC devices, and is of a physical size that lends itself to application within MMIC devices.

A CMOS 77-GHz Receiver Front-End for Automotive Radar

Abstract: This paper presents the design of a receiver (Rx) front-end for automotive radar application operating at 76-77 GHz. The Rx employs a double conversion architecture, which consists of a five-stage low-noise amplifier (LNA), a sub-harmonic mixer (SHM), and a double-balanced passive mixer (PSM). By adopting this architecture, millimeter-wave frequency synthesizer design can be relaxed. In the LNA layout, the output of each stage is positioned close to the input of the follow stage, thus creating a LC resonance load. As a result, complex interstage matching networks is simplified. The SHM driven by a 38-GHz local oscillator (LO) is adopted to avoid push/pull effect and power consumption of the voltage-controlled oscillator. A PSM is utilized for the second conversion since it consumes no dc current and has low flickering noise. To connect the singled-ended LNA and SHM, a 77-GHz balun is designed; and for driving the SHM, two 38-GHz baluns and an in-phase/quadrature coupler to provide quadrature 38-GHz LO are designed. The proposed Rx is implemented in a 65-nm CMOS technology and measurement results show 16-dB voltage gain and 13-dB calculated noise figure while dissipating 23.5 mA from a black 1.2-V supply.

Broadband Active Balun Using Combined Cascode–Cascade Configuration

Abstract: A new configuration is proposed for an active balun, which uses a cascode and cascade pair with the shared input transistor. It is designed in the IBM 8HP 130-nm BiCMOS process, which operates over a broad bandwidth up to 17 GHz where the imbalance of the differential output is less than 1.8 dB in amplitude and less then 10 in phase, over the input's dynamic range of -25-5 dBm, under the dc power consumption of 198.8 mW. The circuit contains no internal dc blocking capacitors so that the bandwidth's lower end frequency best extends as close to dc as possible. The circuit contains only one line inductor with the value of 0.2 nH, and the compacted layout is expected to fit in limited chip areas as small as 0.2 mm times 0.2 mm, which makes them well suited for built-in self-test applications, as well as general differential circuits requiring compact-sized broadband baluns.

A fully integrated 5.3-GHz 2.4-V 0.3-W SiGe bipolar power amplifier with 50-/spl Omega/ output

Abstract: A radio frequency power amplifier for 4.8-5.7 GHz has been realized in a 0.35-/spl mu/m SiGe bipolar technology. The balanced two-stage push-pull power amplifier uses two on-chip transformers as input-balun and for interstage matching. Further, it uses three coils for the integrated LC-output balun and the RF choke. Thus, the power amplifier does not require any external components. At 1.0-V, 1.5-V, and 2.4-V supply voltages, output powers of 17.7 dBm, 21.6 dBm, and 25 dBm are achieved at 5.3 GHz. The respective power-added efficiencies (PAE) are 15%, 22%, and 24%. The small-signal gain is 26 dB. The output 1-dB compression point at 2.4 V is 22 dBm with a PAE of 14%.

Broadband planar wide-scan array employing tightly coupled elements and integrated balun

Abstract: In this paper we present the design, fabrication and demonstration of an X-band phased array capable of wide-angle scanning. A new non-symmetric element for wideband tightly coupled dipole arrays is integrated with a low-profile microstrip balun printed on the array ground plane. The feed connects to the array aperture with vertical twin-wire transmission lines that concurrently perform impedance matching. The proposed element arms are identical near the center feed portion but dissimilar towards the ends, forming a ball-and-cup. A 64 element array prototype is verified experimentally and compared to numerical simulation. The array aperture is placed λ/7 (at 8 GHz) above a ground plane and shown to maintain a VSWR < 2 from 8–12.5 GHz while scanning up to 75° and 60° in E and H-plane, respectively.