Development of low power 2.4 ghz low noise amplifier using forward body bias technique for wireless sensor network

The modern disposable wireless sensor network (WSN) markets have put great demands on a low-power RF receiver. As to operate using only a single battery for a long period of time continuously, these receivers require a high level of energy efficiency. It is also challenging to achieve require system performance in such low power WSN where the maximum power consumption should be lower than 1 mW in range. Therefore, the objectives of this project are to study, propose, design and verify a new technique for low power low noise amplifier (LNA) as to be implemented for WSN applications. A new topology based on forward body bias technique with cascode configuration has been adopted to make the LNA suitable for low power applications using CMOS 0.13 μm Silterra technology. There are two proposed design in this work which are single stage LNA and two stages LNA. For a single stage LNA, a low supply voltage of 0.5 V is used to optimize the trade-offs between gain, noise figure and power consumption. The post layout simulation results indicate that the power consumption of 0.3 mW is achieved with 600 μA of current consumption which is improved about 62.5 % compared to the previous work. The simulated input return loss (S11) is less than -18 dB while the output return loss (S22) is below -15 dB. Besides, the gain (S21) of 9.86 dB, the noise figure (NF) of 5.11 dB and the third-order intercept point (IIP3) of -7.5 dBm at 2.4 GHz is obtained. The calculated figure of merit (FOM) of 4.62 (1/mW) is the highest among the previously published work. For a two stages LNA, a low supply voltage of 0.55 V is employed and drawn 820 μA of total current. The post layout simulation results depict that the power consumption of 0.45 mW is achieved which is improved about 79 % compared to the previous work. The simulated input return loss (S11) is less than -17 dB while the output return loss (S22) is below -12 dB. Other than that, the gain (S21) of 15.1 dB, the noise figure (NF) of 5.9 dB and the thirdorder intercept point (IIP3) of -2 dBm at 2.4 GHz is attained. The calculated figure of merit (FOM) of 4.37 (1/mW) is the highest among the previously published work. Therefore, the proposed LNA is suitable for WSN application.