Design And Study Of PCB-based Wireless Inter-chip Interconnection And Key Devices

With the increasement of chip functions and bus frequency on the printed circuit board(PCB),the chip layout is becoming more and more intensive,the pin number is more and more.Due to the interconnection by chips' pins,the signal integrity(SI)is increasingly affected by the reflection of the signal transmission,the crosstalk between neighboring signals,the parasitic inductance and capacitance,and so on,so the wireless intra / inter-chip interconnection has become the one of the current hottest research fields.This thesis establishes a novel wireless inter-chip interconnection from the theory and experiments,including the wireless signal interconnection and wireless power transmission,where research topic for wireless power transmission applied in between chips has still been not reported so far.Also,this thesis focuses on the design and study of the miniaturized,multi-band bandpass filters which are the key devices in the wireless interconnection.The main works and contributions of this thesis are summarized as follows:(1)The chip-PCB wireless interconnection is proposed,the PCB medium is used as a communication channel,and the chip pins are designed as pin antennas,which replace the previous way of signal transmission–inter-chip wire interconnection.The signals are wirelessly transmitted by PCB medium from one chip to another one;(2)Studied is a chip-PCB wireless interconnection structure with metal films on the top and bottom surfaces of the medium layer,and 20 GHz antennas are designed.According to the knee frequency,the S-parameter matrix of the two antennas is simulated from 0 to 60 GHz,and imported into SNP module in circuits.The 20 GHz sine wave source is loaded into the input port of transmitting antenna,the amplitudes of output signals from the receiving antenna are reduced by about 50% than the ones of input signals.The PRBS source is loaded,rising time and falling time of the eye pattern of the output signals from receiving antenna are increased than input signals,while its width and height are unchanged.It is verified that ultra-wide band digital pulse signals can be transmitted through metal film-metal film chip-PCB wireless interconnection;(3)Studied is a chip-PCB wireless interconnection with mushroom-type metamaterial absorber on the bottom surface of the medium layer and metal film on its top surface,and the maximum absorptance is 61.82%.The NRZ PRBS source is loaded into the input port from transmitting antenna,and the eye pattern of output signals are observed from a virtual oscilloscope at receiving antenna,the closer the distance from the transmitting antenna is,the bigger its “eye” opening is.Compared with the metal film-metal film chip-PCB wireless interconnection structure,the eye pattern of signals through this structure is clearer,and “eye” opening is slightly bigger;(4)Studied is an absorbing layer-absorbing layer chip-PCB wireless interconnection structure,and a single octagonal ring metamaterial absorber is designed with a fractional bandwidth of 1.52% under the absorptance level of 90%,and placed on the top surface and bottom surface of the medium layer.Compared with metal film-metal film one,in this structure,the reflection coefficient and transmission coefficient for two chip pin antennas decrease at the working frequency,but they are improved near the working frequency.S-parameter matrixes for two chip pin antennas are respectively extracted from absorbing layer-absorbing layer / metal film-metal film / open boundary chip-PCB wireless interconnection structures,and imported into corresponding SNP modules in simulation circuits.The PRBS source is added,and the BPSK modulation and demodulation are utilized to compare and analyze BER performances of the three communication systems.Then,a triple-octagonal-ring metamaterial UWB absorber is designed with a fractional bandwidth of 49.4% under the absorptance level of 90%,the frequency ranges from 15.5GHz to 25.68 GHz.UWB absorbers are placed on the top surface and bottom surface of medium layer,which forms a UWB absorber chip-PCB interconnection structure.Compared with open boundary one,the BER performance from this system is closer for the distance range from 10 mm to 20 mm,but as the distance increases,the BER increases faster with a worse performance;(5)Proposed are the hypotheses of chip-supplied wireless power interconnections,and the fundamental of DC-DC wireless transmission is studied.By T-type equivalent network circuit and Z-parameter matrix,self-inductance,mutual-inductance and coupling coefficient are extracted from two coupled inductors.Colpitts-and Hartley-based wireless power interconnection systems are respectively designed,and the half-and full-wave rectifiers are used in the receiving circuits,respectively.Finally,they are fabricated and tested,and the experiments verify that it is feasible for DC-DC wireless interconnection,which provides an important reference for the chip-level design and integration in the future;(6)Studied is the key technology of chip-PCB wireless interconnection,such as the bandpass filter design.Three different SIRs are analyzed to realize dual-and tri-band bandpass filters.The resonator structures and how to form two / three passbands are studied,the effects of different parameters on the center frequencies and bandwidths are discussed.The three filter prototypes are fabricated,measured and compared,which verify the design ideas are right.Based on 65 nm CMOS process,the dual-and tri-band bandpass filters are designed with the corresponding patch structures.It provides a good reference to improving chip-PCB wireless interconnection and chip integrated circuit design.