Design Of Low-voltage AFC And SPI Module In RF Transceiver For WSN

Wireless sensor network(WSN)is a self organizing network system which composed of plenty of micro-sensor nodes.It is mainly used in intelligent home,environmental monitoring,health care and military security etc.With the development of WSN,RF transceiver is proposing higher requirements for the stability and power of frequency synthesizer.As the core module of frequency synthesizer,it is meaningful to design low-voltage auto calibration module(AFC)and serial peripheral interface module(SPI).This thesis introduced the theory of PLL frequency synthesizer.According to IEEE 802.15.4 protocol,the specific requirements of AFC and SPI module are figured out.AFC module uses a counter-based open loop structure and the PS counter is turned off to reduce the error when AFC works.At the same time,the fast AFC algorithm is used to reduce AFC loop locking time.SPI module operates in slave mode and can write to or read from an external register.AFC and SPI module both use semi-custom digital circuit design method.The RTL code written,functional simulation results,synthesis,synthesis results,layout design and post simulation results are given in this thesis.The two modules are tape-outed in TSMC 0.18?m RF CMOS process.With 1.0V power supply,the measured results show that the AFC loop works properly,the locking frequency range is 4.8-5.0GHz,the loop locking time is 16.6?s in worst working case,the frequency deviation is 64MHz and the current is 180.8?A.SPI module can achieve right read and write function.A total of 16 external registers can be read and written,2 external registers can only be read and the current is 300.5pA.The designed low-voltage AFC module and SPI module in this thesis meets the requirements of RF transceiver for WSN and have been applied in RF transceiver chip for WSN.