HBT MMIC Power Amplifier Research Articles

A GSM/EDGE Dual-Mode, Triple-Band InGaP HBT MMIC Power Amplifier Module

This paper describes a 3.5V operation InGaP HBT MMIC power amplifier module for use in GSM/EDGE dual-mode, 900/1800/1900 MHz triple band handset applications. Conventional GSM amplifiers have a high linear gain of 40 dB or more to realize efficiency operation in large gain compression state exceeding at least 5 dB. On the other hand, an EDGE amplifier needs a linear operation to prevent signal distortion. This means that a high linear gain amplifier cannot be applied to the EDGE amplifier, because the high gain leads to the high noise power in the receive band (Rx-noise). In order to solve this problem, we have changed the linear gain of the amplifier between GSM and EDGE mode. In EDGE mode, the stage number of the amplifier changes from three to two. To reduce a high gain, the first stage transistors in the amplifier is bypassed through the diode switches. This newly proposed bypass circuit enables a high gain in GSM mode and a low gain in EDGE, thus allowing the amplifier to operate with high efficiency in both modes while satisfying the Rx-noise specification. In conclusion, with diode switches and a band select switch built on the MMIC, the module delivers a P out of 35.5 dBm and a PAE of about 50% for GSM900, a 33.4 dBm P out and a 45% PAE for GSM1800/1900. While satisfying an error vector magnitude (EVM) of less than 4% and a receive-band noise power of less than -85dBm/100kHz, the module also delivers a 29.5 dBm P out and a PAE of over 25% for EDGE900, a 28.5 dBm P our and a PAE of over 25% for EDGE 1800/1900.

MMIC power amplifier with on-chip bias current controlling circuit for W-CDMA mobile handset

A new on-chip bias current controlling circuit for efficiency enhancement has been devised and implemented to a W-CDMA InGaP/GaAs HBT MMIC power amplifier. It supplies a quiescent current of 86 (54) mA for a high (low) power mode operation. The reduced quiescent current at the low power mode operation improves the PAE as much as 21.6% at the output power of 20 dBm and 59.2% under 0 dBm output power compared to the high power mode operation only.

High-efficiency GaInP/GaAs HBT MMIC power amplifier with up to 9 W output power at 10 GHz

Monolithic power amplifiers using adequately ballasted high-efficiency GaInP/GaAs heterojunction bipolar transistors (HBT's) have been designed, fabricated, and tested. A maximum output power of 9 W with a power-added efficiency (PAE) of 42% and peak power-added efficiencies of 45% have been achieved at 10 GHz under critical long pulse conditions (pulse width=100 μs, duty cycle=10%). To our knowledge these results represent the best performance of any GaInP/GaAs HBT MMIC power amplifier considering efficiency, output power, operation frequency, and pulse conditions.

Optimization of the HBT and bump configuration for bump heat sink structure and application to HBT power MMICs

Suitable HBT and bump configuration for the BHS (Bump Heat Sink) structure are experimentally investigated. The best results in terms of thermal and electrical characteristics is obtained from the combination of a single emitter finger and an “H” shaped bump. Power HBTs are demonstrated with typical power added efficiencies η add of 70% at 8.0 W and a linear power vs transistor size relation up to 10 W at 0.9 GHz CW with V cc = 6 V, using the optimized structure. A three-stage HBT MMIC power amplifier and a power amplifier module for GSM class 4 are demonstrated with η add of 53% at 5.0 W, for V cc = 6 V CW operation, also using the optimized structure.

First demonstration of high-power GaInP/GaAs HBT MMIC power amplifier with 9.9 W output power at X-band

We report for the first time the large-signal power performance of a MMIC amplifier based on GaInP/GaAs HBT's. A output power of 9.9 W and power-added efficiency of more than 30% are measured at X-band. These results compare favorably with those measured from AlGaAs/GaAs HBT's, demonstrating that GaInP/GaAs HBT's are suitable for microwave power applications.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

A 2 watt, 8-14 GHz HBT power MMIC with 20 dB gain and &amp;lt;40% power-added efficiency

A two-stage, 8-14 GHz high-efficiency AlGaAs/GaAs HBT MMIC power amplifier has been designed and tested. At 7 V collector bias, this common-emitter monolithic amplifier has achieved 20 dB gain, 33 dBm (CW) output power, and >40% power-added efficiency over the 8-14 GHz band. The amplifier is designed for 25 /spl Omega/ input and output impedance, and all the matching networks, as well as biasing circuits, are contained within this HBT MMIC. To our knowledge, this is the highest efficiency, the highest gain, and the highest output power reported for any monolithic power amplifier covering a 6 GHz bandwidth in the X-Ku band. >

A 1.8-W, 6-18-GHz HBT MMIC power amplifier with 10-dB gain and 37% peak power-added efficiency

A two-stage 6-18-GHz high-efficiency AlGaAs-GaAs HBT MMIC power amplifier has been designed and tested. At 7-V collector bias, this fully matched monolithic amplifier delivered an output power of 1.8+or-0.6 W over the band. The peak output power was 2.45 W at 13 GHz with an associated gain of 11.1 dB and 36.7% power-added efficiency (PAE). Amplifiers from five different wafers showed similar performance.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>