A0923356 ???

1
????????

• A0923356 ???

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??

• ??????(Spread spectrum)
• ??(FHFrequency hopping)
• ??????(Orthogonal hopping sequence)
• ??????(DS?DSSSDirect-sequence spread spectrum)
• ?????
• ??????(OFDMOrthogonal frequency division
  multiplexing)
• OFDM??

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??????(Spread spectrum)

• ???????????????
• ??
• ???????????(Multipath fading)???????
• ????????
• ?????????
• ????????????,?????????

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??????(Multipath fading)

• ???????????,??????,???????????????????????

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??(FHFrequency hopping)

• ?????????,???????,??????????????Blue tooth(79???)?

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??????(Orthogonal hopping sequence)

• ???????????,????????????????,????????
• ???????????,????(Orthogonal)?

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??????(DS?DSSSDirect-sequence spread spectrum)

• ???????????,??????RF(Radio frequency)?????????(???
  ???)???,??????????,?FH???????802.11b?

8
?????
?????(Spreading Code)???????????????,???????????,?
??11???????????????????11??????
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??????(OFDMOrthogonal frequency division
multiplexing)

• ??????????????????,??????,?????????????OFDM???????
  ?????????????????????????
• OFDM?????
• ???? ??????(DAB)?????(DTV)
• ?????? IEEE 802.11 a/g?HIPERLAN/2
• ????????? IEEE 802.16(WiMAX)
• ?????????(ADSL)

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OFDM??

• ?????????(FFTfast Fourier Transform)???????,?????
  ??????????

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Thank you for your listening