ﻃﺮاﺣﯽ و ﺷﺒﯿﻪﺳﺎزي ﺗﻘﻮﯾﺖﮐﻨﻨﺪه ﮐﻢﻧﻮﯾﺰ ﮐﻢﻣﺼﺮف ﺑﺮاي ﮐﺎرﺑﺮدﻫﺎي رادﯾﻮﺷﻨﺎﺧﺘﯽ

Design and Simulation of Low Power Low Noise Amplifier For Cognitive Radio Applications

ﭼﮑﯿﺪه: رادﯾﻮﺷﻨﺎﺧﺘﯽ ﺑﻪ ﻋﻨﻮان ﯾﮏ ﺳﯿﺴﺘﻢ ارﺗﺒﺎﻃﯽ ﺑﯽﺳﯿﻢ ﻓﺮاﭘﻬﻦﺑﺎﻧﺪ ﮐﻪ ﺑﻪ ﻃﻮر ﻫﻮﺷﻤﻨﺪ و ﺑﺎ روش ﻧﻈﺎرت ﭘﻮﯾﺎ ﻃﯿﻒ ﻓﺮﮐﺎﻧﺴﯽ ﻣﻮﺟﻮد را ﺑﻬﯿﻨﻪ ﻣﯽﮐﻨﺪ. ﮔﯿﺮﻧﺪه ﭼﻨﯿﻦ ﺳﯿﺴﺘﻤﯽ ﻧﯿﺎز ﺑﻪ ﯾﮏ ﺗﻘﻮﯾﺖﮐﻨﻨﺪه ﮐﻢﻧﻮﯾﺰ ﻓﺮاﭘﻬﻦﺑﺎﻧﺪ )از MHz 50 ﺗﺎGHz 10( دارد. در اﯾﻦ ﮐﺎر ﯾﮏ ﺗﻘﻮﯾﺖﮐﻨﻨﺪه ﮐﻢﻧﻮﯾﺰ ﮐﻢﻣﺼﺮف ﻓﺮاﭘﻬﻦﺑﺎﻧﺪ ﻃﺮاﺣﯽ ﺷﺪه ﮐﻪ داراي ﺳﺎﺧﺘﺎر ﺷﺒﻪ ﺗﻔﺎﺿﻠﯽ و ﺳﻠﻒ ﻓﻌﺎل اﺳﺖ. ﺑﮑﺎرﮔﯿﺮي ﻣﺪارﻫﺎي ﻓﻌﺎل ﻣﺒﺘﻨﯽ ﺑﺮ ﻓﻨﺎوري CMOS ﮐﻪ رﻓﺘﺎر ﺳﻠﻔﯽ از ﺧﻮد ﻧﺸﺎن ﻣﯽدﻫﻨﺪ ﺑﻪ ﻋﻨﻮان ﺳﻠﻒ ﻓﻌﺎل، ﻋﻼوه ﺑﺮ اﻓﺰاﯾﺶ ﭘﻬﻨﺎيﺑﺎﻧﺪ ﺗﻘﻮﯾﺖﮐﻨﻨﺪه و ﮐﺎﻫﺶ ﺳﻄﺢ ﺗﺮاﺷﻪ، داراي ﺑﻬﺮه ذاﺗﯽ ﺑﻮده و ﺑﻪ ﻋﻠﺖ داﺷﺘﻦ ﺿﺮﯾﺐ ﮐﯿﻔﯿﺖ ﺑﺎﻻ، ﻗﺎﺑﻠﯿﺖ ﺗﻨﻈﯿﻢ اﻧﺪوﮐﺘﺎﻧﺲ و ﻓﺮﮐﺎﻧﺲ را ﻧﯿﺰ دارا ﻣﯽ-ﺑﺎﺷﺪ. LNA ﭘﯿﺸﻨﻬﺎدي ﺑﺎ اﺗﺼﺎل ﺿﺮﺑﺪري دو ﺳﻠﻒ ﻓﻌﺎل ﻃﺮاﺣﯽ ﺷﺪه ﮐﻪ ﻋﻼوه ﺑﺮ اﻓﺰاﯾﺶ ﭘﻬﻨﺎي ﺑﺎﻧﺪ ﻓﺮﮐﺎﻧﺴﯽ، ﺑﻪ ﻋﻠﺖ ﺷﺮاﯾﻂ ﺷﺒﻪ ﺗﻔﺎﺿﻠﯽ، ﺑﺎ اﻓﺰاﯾﺶ ﻫﺪاﯾﺖ اﻧﺘﻘﺎﻟﯽ ﺗﺮاﻧﺰﯾﺴﺘﻮرﻫﺎ، ﻋﻼوه ﺑﺮ ﮐﺎﻫﺶ ﺗﻮان ﻣﺼﺮﻓﯽ، ﺳﺒﺐ ﮐﺎﻫﺶ ﻋﺪد ﻧﻮﯾﺰ ﻣﺪار ﻣﯽﺷﻮد. ﻧﺘﺎﯾﺞ ﺷﺒﯿﻪﺳﺎزي ﺑﺎ ﻓﺮآﯾﻨﺪ 0/18µm CMOS ﻧﺸﺎن ﻣﯽدﻫﺪ ﮐﻪ LNA ﭘﯿﺸﻨﻬﺎدي ﺑﻪ ﺗﻐﯿﯿﺮات ﻋﺪد ﻧﻮﯾﺰ از dB 3-7 و ﺗﻄﺒﯿﻖ ورودي ﺑﻬﺘﺮ از 10dB- در ﺑﺎﻧﺪ GHz 0/05-10 دﺳﺖ ﯾﺎﻓﺘﻪ اﺳﺖ. ﺗﻐﯿﯿﺮات ﺑﻬﺮه وﻟﺘﺎژ ازdB 16/5-19 و ﻧﻘﻄﻪ ﺗﻘﺎﻃﻊ ﻣﺮﺗﺒﻪ ﺳﻮم 6/7dBm- اﺳﺖ. ﺗﻮان ﻣﺼﺮﻓﯽ ﻣﺪار اﺻﻠﯽ mW 1/98 ﺑﺎ ﻣﻨﺒﻊ ﺗﻐﺬﯾﻪ V 1/8 اﺳﺖ.

Cognitive radio is well known as an ultra-wideband communication system that intelligently optimizes the available frequency spectrum by implementing the dynamic spectrum monitoring method. The receiver of such a system requires an ultra-wideband low noise amplifier (from 50 MHz to 10 GHz). In this work, a low power ultra-wideband low noise amplifier is proposed by quasi-differential structure and active inductors. Using active circuits as inductors, in addition to expanding the amplifier bandwidth and reducing the chip area, have an inherent gain and due to their high quality factor, have the ability to adjust the inductance and frequency. In addition, the quasi-differential structure increases the transconductance of transistors and reduces both power consumption and noise figure of this circuit. The simulation results in a 0.18 µm CMOS process show that the proposed LNA achieved NF changes 3-7 dB and input matching less than -10 dB in the 0.05-10 GHz band. The voltage gain changes from 16.5-19 dB and third-order intercept point is -6.7 dBm. The power consumption of the main circuit is 1.98 mW with 1.8 V power supply.