The development of a high performance wideband radio frequency （RF） transceiver used in the next generation mobile communication system is presented. The developed RF transceiver operates in the 6 to 6.3 GHz band an...The development of a high performance wideband radio frequency （RF） transceiver used in the next generation mobile communication system is presented. The developed RF transceiver operates in the 6 to 6.3 GHz band and the channel bandwidth is up to 100 MHz. It operates in the time division duplex （TDD） mode and supports the multiple-input multipleoutput （MIMO） technique for the international mobile telecommunications （IMT）-advanced systems. The classical superheterodyne scheme is employed to achieve optimal performance. Design issues of the essential components such as low noise amplifier, power amplifier and local oscillators are described in detail. Measurement results show that the maximum linear output power of the RF transceiver is above 23 dBm, and the gain and noise figure of the low noise amplifier is around 24 dB and below 1 dB, respectively. Furthermore, the error vector magnitude （EVM） measurement shows that the performance of the developed RF transceiver is well beyond the requirements of the long term evolution （LTE）-advanced system. With up to 8 x 8 MIMO configuration, the RF transceiver supports more than a 1 Gbit/s data rate in field tests.展开更多
A new 125mm UHV/CVD SiGe/Si epitaxy equipment SGE500 capable of commercialization is constructed and device-level SiGe HBT material is grown.A polysilicon emitter (PolyE) double mesa microwave power SiGe HBT showing e...A new 125mm UHV/CVD SiGe/Si epitaxy equipment SGE500 capable of commercialization is constructed and device-level SiGe HBT material is grown.A polysilicon emitter (PolyE) double mesa microwave power SiGe HBT showing excellent low current DC characteristics with β=60@V CE/I C=9.0V/300μA,β=100@5V/50mA,BV CBO=22V,f t/f max=5.4GHz/7.7GHz@3V/10mA is demonstrated.The PolyE SiGe HBT needs only 6 lithographical steps and cancels the growth of the thick emitter epitaxy layer,both of which show great potential for volume production.A 60-finger class-A SiGe linear power amplifer (PA) w ith 22dBm of 1dB compress point output power (P 1dB),11dB of power gain (G p) and 26.1% of power added efficiency (PAE) @900MHz,3.5V/0.2A is demonstrated.Another 120-finger class-A SiGe PA with 33.3dBm (2.1W) of P out,10.3dB of G p and 33.9% of PAE @900MHz,11V/0.52A is also demonstrated.展开更多
To reduce the number of digital predistortion coefficients, a step memory polynomial （SMP）predistorter is presented. The number of predistortion coefficients is decreased by adjusting the maximum nonlinear order for...To reduce the number of digital predistortion coefficients, a step memory polynomial （SMP）predistorter is presented. The number of predistortion coefficients is decreased by adjusting the maximum nonlinear order for different memory orders in the traditional memory polynomial （MP）predistorter. The proposed SNIP predistorter is identified by an offline learning structure on which the coefficients can be extracted directly from the sampled input and output of a PA. Simulation results show that the SMP predistorter is not tied to a particular PA model and is, therefore, robust. The effectiveness of the SMP predistorter is demonstrated by simulations and experiments on an MP model, a parallel Wiener model, a Wiener-Hammerstein model, a sparsedelay memory polynomial model and a real PA which is fabricated based on the Freescale LDMOSFET MRF21030. Compared with the traditional MP predistorter, the SMP predistorter can reduce the number of coefficients by 60%.展开更多
4H-SiC MESFETs are fabricated on semi-insulating SiC substrates. Key processes are optimized to obtain better device performance. A microwave power amplifier is demonstrated from a 1mm SiC MESFET for S band operation....4H-SiC MESFETs are fabricated on semi-insulating SiC substrates. Key processes are optimized to obtain better device performance. A microwave power amplifier is demonstrated from a 1mm SiC MESFET for S band operation. When operated at a drain voltage of 64V, the amplifier shows an output power of 4.09W, a gain of 9.3dB,and a power added efficiency of 31.3%.展开更多
A 4-12GHz wideband power amplifier,using a balanced configuration with a strip line Lange coupler, is designed and fabricated. This power amplifier shows a maximum continuous wave output power of 29.5dBm at 8GHz cente...A 4-12GHz wideband power amplifier,using a balanced configuration with a strip line Lange coupler, is designed and fabricated. This power amplifier shows a maximum continuous wave output power of 29.5dBm at 8GHz center frequency with an associated gain of 8.5dB and a gain flatness of ＋ /- 0.6dB in the 4-12GHz frequency range.展开更多
A power amplifier MIC with power combining based on AlGaN/GaN HEMTs was fabricated and measured. The amplifier consists of four 10 × 120μm transistors. A Wilkinson splitters and combining were used to divide and...A power amplifier MIC with power combining based on AlGaN/GaN HEMTs was fabricated and measured. The amplifier consists of four 10 × 120μm transistors. A Wilkinson splitters and combining were used to divide and combine the power. By biasing the amplifier at VDS = 40V, IDS = 0.9A, a maximum CW output power of 41.4dBm with a maximum power added efficiency （PAE） of 32.54% and a power combine efficiency of 69% was achieved at 5.4GHz.展开更多
Good performance SiGe power amplifiers applicable to wireless communications are demonstrated.The output power can reach more than 30dBm in class B mode.And in class AB mode,the output power at 1dB compression point (...Good performance SiGe power amplifiers applicable to wireless communications are demonstrated.The output power can reach more than 30dBm in class B mode.And in class AB mode,the output power at 1dB compression point ( P 1dB ) is 24dBm,the output third order intercept (TOI) power is 39dBm under V cc of 4V.The highest power added efficiency (PAE) and PAE at 1dB compression point are 34% and 25%,respectively.The adjacent channel power rejection for CDMA signal is more than 42dBc,which complies with IS95 specification.展开更多
基金The National Natural Science Foundation of China (No.60702027,60921063)the National Basic Research Program of China(973 Program)(No.2010CB327400)the National Science and Technology Major Project of Ministry of Science and Technology of China(No.2010ZX03007-001-01,2011ZX03004-001)
文摘The development of a high performance wideband radio frequency （RF） transceiver used in the next generation mobile communication system is presented. The developed RF transceiver operates in the 6 to 6.3 GHz band and the channel bandwidth is up to 100 MHz. It operates in the time division duplex （TDD） mode and supports the multiple-input multipleoutput （MIMO） technique for the international mobile telecommunications （IMT）-advanced systems. The classical superheterodyne scheme is employed to achieve optimal performance. Design issues of the essential components such as low noise amplifier, power amplifier and local oscillators are described in detail. Measurement results show that the maximum linear output power of the RF transceiver is above 23 dBm, and the gain and noise figure of the low noise amplifier is around 24 dB and below 1 dB, respectively. Furthermore, the error vector magnitude （EVM） measurement shows that the performance of the developed RF transceiver is well beyond the requirements of the long term evolution （LTE）-advanced system. With up to 8 x 8 MIMO configuration, the RF transceiver supports more than a 1 Gbit/s data rate in field tests.
文摘A new 125mm UHV/CVD SiGe/Si epitaxy equipment SGE500 capable of commercialization is constructed and device-level SiGe HBT material is grown.A polysilicon emitter (PolyE) double mesa microwave power SiGe HBT showing excellent low current DC characteristics with β=60@V CE/I C=9.0V/300μA,β=100@5V/50mA,BV CBO=22V,f t/f max=5.4GHz/7.7GHz@3V/10mA is demonstrated.The PolyE SiGe HBT needs only 6 lithographical steps and cancels the growth of the thick emitter epitaxy layer,both of which show great potential for volume production.A 60-finger class-A SiGe linear power amplifer (PA) w ith 22dBm of 1dB compress point output power (P 1dB),11dB of power gain (G p) and 26.1% of power added efficiency (PAE) @900MHz,3.5V/0.2A is demonstrated.Another 120-finger class-A SiGe PA with 33.3dBm (2.1W) of P out,10.3dB of G p and 33.9% of PAE @900MHz,11V/0.52A is also demonstrated.
基金The National High Technology Research and Development Program of China (863 Program) (No.2008AA01Z211)the Project of Industry-Academia-Research Demonstration Base of Education Ministry of Guangdong Province (No.2007B090200012)
文摘To reduce the number of digital predistortion coefficients, a step memory polynomial （SMP）predistorter is presented. The number of predistortion coefficients is decreased by adjusting the maximum nonlinear order for different memory orders in the traditional memory polynomial （MP）predistorter. The proposed SNIP predistorter is identified by an offline learning structure on which the coefficients can be extracted directly from the sampled input and output of a PA. Simulation results show that the SMP predistorter is not tied to a particular PA model and is, therefore, robust. The effectiveness of the SMP predistorter is demonstrated by simulations and experiments on an MP model, a parallel Wiener model, a Wiener-Hammerstein model, a sparsedelay memory polynomial model and a real PA which is fabricated based on the Freescale LDMOSFET MRF21030. Compared with the traditional MP predistorter, the SMP predistorter can reduce the number of coefficients by 60%.
文摘4H-SiC MESFETs are fabricated on semi-insulating SiC substrates. Key processes are optimized to obtain better device performance. A microwave power amplifier is demonstrated from a 1mm SiC MESFET for S band operation. When operated at a drain voltage of 64V, the amplifier shows an output power of 4.09W, a gain of 9.3dB,and a power added efficiency of 31.3%.
文摘A 4-12GHz wideband power amplifier,using a balanced configuration with a strip line Lange coupler, is designed and fabricated. This power amplifier shows a maximum continuous wave output power of 29.5dBm at 8GHz center frequency with an associated gain of 8.5dB and a gain flatness of ＋ /- 0.6dB in the 4-12GHz frequency range.
文摘A power amplifier MIC with power combining based on AlGaN/GaN HEMTs was fabricated and measured. The amplifier consists of four 10 × 120μm transistors. A Wilkinson splitters and combining were used to divide and combine the power. By biasing the amplifier at VDS = 40V, IDS = 0.9A, a maximum CW output power of 41.4dBm with a maximum power added efficiency （PAE） of 32.54% and a power combine efficiency of 69% was achieved at 5.4GHz.
文摘Good performance SiGe power amplifiers applicable to wireless communications are demonstrated.The output power can reach more than 30dBm in class B mode.And in class AB mode,the output power at 1dB compression point ( P 1dB ) is 24dBm,the output third order intercept (TOI) power is 39dBm under V cc of 4V.The highest power added efficiency (PAE) and PAE at 1dB compression point are 34% and 25%,respectively.The adjacent channel power rejection for CDMA signal is more than 42dBc,which complies with IS95 specification.
