ã¯ããã«
è€çŽ ãããµãŒããŒãIFã¢ãŒããã¯ãã£ãå é²çãªã¢ã«ãŽãªãºã ã®éã«ã¯è峿·±ãçžäºé¢ä¿ããããŸããæ¬çš¿ã§ã¯ããŸãããããã®åºæ¬çãªåçãšã·ã¹ãã èšèšã«ãããæçšæ§ã«ã€ããŠèª¬æããŸãããã®ããã§ãããã3ã€ã®çžäºé¢ä¿ã«é¢ããèå¯ãå ããŸãã
ãšã¬ã¯ãããã¯ã¹ã®åéã«ãããŠãRFæè¡ãâé»éè¡âã®ããã«æ±ãããããšã¯å°ãªããããŸãããæ°åŠãšååŠãå Žåã«ãã£ãŠã¯åãªã詊è¡é¯èª€ãè€éã«çµ¡ã¿åãããšããããŸããRFæè¡ã¯å€ãã®åªç§ãªæè¡è ã«äžå®ãããããååšã«ããªãåŸãŸããå®éããã®è©³çްã«ãŸã§èžã¿èŸŒãããšãªããæŠèŠãçè§£ããããšã§çŽåŸããŠãã人ãããããããŸããRFæè¡ã«é¢ããæç®ã¯ããã®æ ¹åºã«ããæŠå¿µãæç€ºããããšãªããäžè¶³é£ã³ã«çè«ãæ°åŠçãªèª¬æãå§ãããã®ãå°ãªããããŸããã
RF察å¿ã®è€çŽ ãããµãŒã®è¬ãè§£ã
å³1ã«ç€ºããã®ã¯ãè€çŽ ãããµãŒã䜿ã£ãŠæ§æããã¢ããã³ã³ããŒã¿ïŒãã©ã³ã¹ããã¿ïŒ ã§ãã2ã€ã®äžŠåãã¹ïŒãã£ã³ãã«ïŒã®ããããã«ãããµãŒãé 眮ãããŠããŸãããããã®ãã¹ã«ã¯ãå ±éã®å±éšçºæ¯åšïŒLOïŒ ããäœçžã90°ç°ãªãä¿¡å·ãäŸçµŠãããŸãã2ã€ã®ãããµãŒããã®åºåã¯å ç®ã¢ã³ãã§è¶³ãåããããææã®RFåºåãçæãããŸãã

ãã®æ§æã¯ãã¢ããªã±ãŒã·ã§ã³ã«ãã£ãŠã¯éåžžã«æçšã§ããå³2ã«ç€ºãããã«ãããŒã³ïŒ åäžåšæ³¢æ°ã®ä¿¡å·ïŒ ãIãã£ã³ãã«ã ãã«å ¥åããQãã£ã³ãã«ã®å ¥åã¯é§åããªãããã«ãããšããŸããIãã£ã³ãã«ã«å ¥åããããŒã³ã®åšæ³¢æ°ãxMHzã§ãããšãããšãIãã£ã³ãã«ã®ãããµãŒã¯ïŒ»LOã®åšæ³¢æ°ïŒœ ± x ã®åºåãçæããŸããäžæ¹ãQãã£ã³ãã«ã®å ¥åã«ã¯ä¿¡å·ã¯å°å ããŠããªãã®ã§ãQãã£ã³ãã«ã®ãããµãŒã¯ç©ºã®ã¹ãã¯ãã«ãçæããããšã«ãªããŸãããã®çµæãIãã£ã³ãã«ã®ãããµãŒã®åºåããã®ãŸãŸRFåºåãšãªããŸãã

次ã«ãåšæ³¢æ°ãxã®ããŒã³ãQãã£ã³ãã«ã«ã ãå ¥åãããšããŸãïŒå³3ïŒããã®å ŽåãQãã£ã³ãã«ã®ãããµãŒã¯ïŒ»LOã®åšæ³¢æ°ïŒœÂ±ïŒ»xã®ä¿¡å·ãåºåããŸããIãã£ã³ãã«ã«äœãå ¥åããŠããªããã°ãIãã£ã³ãã«ã®ãããµãŒã®åºåã«ã¯äœãçæãããŸããããã®çµæãQãã£ã³ãã«ã®ãããµãŒããã®åºåããã®ãŸãŸRFåºåã«ãªããŸãã

å³2ãšå³3ã®åºåã¯ãäžèŠãããšãŸã£ããåãã§ããããã«æãããããããŸãããããããå®éã«ã¯å€§ããç°ãªãç¹ããããŸããããã¯äœçžã§ããå³4ã«ç€ºãããã«ãI/Qäž¡ãã£ã³ãã«ã«åãããŒã³ãå ¥åãããšããŸãããã ããããããã®ããŒã³ã«ã¯90°ã®äœçžå·®ãæããããšä»®å®ããŸãã

ãããµãŒã®åºåãããèŠããšãLOåšæ³¢æ°ïŒœ+ïŒ»å ¥ååšæ³¢æ°ïŒœã®ä¿¡å·ã¯åçžãLOåšæ³¢æ°ïŒœ-ïŒ»å ¥ååšæ³¢æ°ïŒœã®ä¿¡å·ã¯éçžã§ããããšãããããŸãããã®ãããLOã®äžåŽïŒ åšæ³¢æ°ãé«ãïŒ ã®ããŒã³ã¯å ç®ãããLOã®äžåŽïŒåšæ³¢æ°ãäœãïŒã®ããŒã³ã¯çžæ®ºãããŸããã€ãŸãããã£ã«ã¿åŠçãè¡ããªããŠããããŒã³ïŒãµã€ããã³ãïŒã®1ã€ã¯é€å»ãããLOåšæ³¢æ°ã®äžåŽã®åºåã ããçæããããšããããšã§ãã
å³4ã®äŸã§ã¯ãIãã£ã³ãã«ã®ä¿¡å·ã¯Qãã£ã³ãã«ã®ä¿¡å·ããäœçžã90°é²ãã§ããŸããQãã£ã³ãã«ã®ä¿¡å·ãIãã£ã³ãã«ãã90°é²ãããã«æ§æã倿Žããå Žåããåæ§ã«å ç®ãšçžæ®ºãè¡ãããã¯ãã§ãããã ãããã®å Žåã«ã¯LOã®äžåŽã®ä¿¡å·ã ããåºåãããŸãã

å³5ã«ç€ºããã®ã¯ãå®éšã«ãã£ãŠè€çŽ ãã©ã³ã¹ããã¿ã®åºåãæž¬å®ããçµæã§ããå·Šã®ã°ã©ãã¯ãIãã£ã³ãã«ã®ä¿¡å·ãQãã£ã³ãã«ã®ä¿¡å·ãã90°é²ãã§ããç¶æ ã衚ããŠããŸãããã®æ¡ä»¶ã§ã¯åºåããŒã³ã¯LOã®äžåŽã«çŸããŸããéã«ãå³ã®ã°ã©ãã¯ãQãã£ã³ãã«ã®ä¿¡å·ãIãã£ã³ãã«ã®ä¿¡å·ãã90°é²ãã§ããå Žåã®çµæã§ããåºåããŒã³ã¯LOã®äžåŽã«çŸããŠããŸãã
çè«çã«ã¯ãLOã®çåŽã ãã«å šãŠã®ãšãã«ã®ãŒãååšããç¶æ ãäœããã¯ãã§ããããããå³5ã®å®éšçµæã®ãšãããå®éã«ã¯LOã®ããäžæ¹ã®åŽã®ãšãã«ã®ãŒãå®å šã«é€å»ãããããšã¯ãªããã€ã¡ãŒãžãšåŒã°ãããšãã«ã®ãŒãæ®åããŸãããŸããLOã®åšæ³¢æ°ã«ããLOãªãŒã¯ïŒLOLïŒãšããŠç¥ããããšãã«ã®ãŒãçŸããããšã«ã泚æããŠãã ãããããã«ãææã®ä¿¡å·ã®é«èª¿æ³¢ãçããŠããŸãããããã«ã€ããŠã¯æ¬çš¿ã§ã¯è§ŠããŸããã
å®å šã«ã€ã¡ãŒãžãé€å»ããã«ã¯ãI/Qäž¡ãã£ã³ãã«ã®ãããµãŒã®åºåã¯æ¯å¹ ããŸã£ããåãã§ããã€LOã®ã€ã¡ãŒãžåŽã«ãããããããã®åºåã®äœçžã¯æ£ç¢ºã«180°ç°ãªã£ãŠããå¿ èŠããããŸããäœçžãšæ¯å¹ ã®èŠä»¶ãæºããããŠããªããã°ãå³4ã§ç€ºããå ç®/é€å»ã®åŠçã¯äžå®å šãªãã®ãšãªããåšæ³¢æ°ã€ã¡ãŒãžãšããŠãšãã«ã®ãŒãæ®åããŸãã
äºæ³ãããçµæ
åäžã®ãããµãŒã䜿çšããåŸæ¥ã®ã¢ãŒããã¯ãã£ã§ã¯ãLOã®äž¡åŽã«ä¿¡å·æåãçæãããŸãããã®ãããéä¿¡ãè¡ãåã«ãµã€ããã³ãã®äžæ¹ãåãé€ãå¿ èŠããããŸãããéåžžãããã«ã¯ãã³ããã¹ã»ãã£ã«ã¿ã䜿çšããŸãããã®ãã£ã«ã¿ã¯ãææã®ä¿¡å·ã«åœ±é¿ãåãŒãããšãªãäžèŠãªã€ã¡ãŒãžä¿¡å·ãé€å»ã§ããããŒã«ãªãç¹æ§ãæããŠããªããã°ãªããŸããã

ã€ã¡ãŒãžãšææã®ä¿¡å·ã®ééã¯ããã£ã«ã¿ã®èŠä»¶ã«å¯ŸããŠçŽæ¥åœ±é¿ãåãŒããŸããééãåºããã°ãã·ã³ãã«ã§ããŒã«ãªããç·©ãããªäœã³ã¹ãã®ãã£ã«ã¿ã䜿çšã§ããŸããäžæ¹ãééãçãå Žåã«ã¯ãæ¥å³»ãªå¿çã®ãã£ã«ã¿ã䜿ããªããã°ãªããŸããããã®ãããéåžžã¯å€æ¥µãã£ã«ã¿ãSAWïŒåŒŸæ§è¡šé¢æ³¢ïŒãã£ã«ã¿ã䜿çšãããŸããã€ã¡ãŒãžãšææã®ä¿¡å·ã®ééã¯ãã€ã¡ãŒãžãææã®ä¿¡å·ã«åœ±é¿ãåãŒãããšãªãé€å»ã§ããããã«ç¢ºä¿ããªããã°ãªããŸããããŸãããã®ééã¯ãã£ã«ã¿ã®è€éããšã³ã¹ãã«åæ¯äŸãããšèšãããšãã§ããã§ããããããã«ãLOã®åšæ³¢æ°ãå¯å€ã§ããå Žåããã£ã«ã¿ã察å¿åšæ³¢æ°ã調æŽã§ãããã®ã«ããªããã°ãªããŸãããããã«ãã£ãŠãã£ã«ã¿ã¯ããã«è€éåããããšã«ãªããŸãã
ã€ã¡ãŒãžãšææã®ä¿¡å·ã®ééã¯ããããµãŒã«äžããä¿¡å·ã«ãã£ãŠæ±ºãŸããŸããå³6ã§ã¯ã垯åå¹ ã10MHzã§ãDCãã10MHzã·ããããäœçœ®ã«ããä¿¡å·ãäŸã«ãšã£ãŠããŸãããã®å ŽåããããµãŒã®åºåã§ã¯ãææã®ä¿¡å·ãã20MHzé¢ãããšããã«ã€ã¡ãŒãžãçæãããŸãããã®æ§æã«ãããŠã10MHzå¹ ã®ææã®ä¿¡å·ãåºåãšããŠåŸãã«ã¯ããããµãŒã«å¯ŸããŠ20MHzã®ããŒã¹ãã³ãä¿¡å·ãã¹ãèšããå¿ èŠããããŸãããããŒã¹ãã³ã垯åå¹ ã®ãã¡10MHzã¯äœ¿çšããããããµãŒåè·¯ã«å¯Ÿããã€ã³ã¿ãŒãã§ãŒã¹ã®ããŒã¿ã¬ãŒãã¯å¿ èŠä»¥äžã«é«ããªããŸãã
å³5ã§ç€ºãããããªè€çŽ ãããµãŒã®ã¢ãŒããã¯ãã£ã§ã¯ãå€éšã®ãã£ã«ã¿åŠçã䜿ãããšãªãã€ã¡ãŒãžãé€å»ã§ããããšãããããŸãããŸãããŒãIFã¢ãŒããã¯ãã£ã§ã¯ãä¿¡å·ãã¹ã§åŠçãã垯åå¹ ããææã®ä¿¡å·ã®åž¯åå¹ ãšçãããªãããã«å¹çãæé©åããããšãã§ããŸããå³7ã¯ããã®å®çŸæ¹æ³ã瀺ããæŠå¿µå³ã§ããå è¿°ããããã«ãIãã£ã³ãã«ã®ä¿¡å·ãQãã£ã³ãã«ã®ä¿¡å·ããäœçžã90°é²ãã§ããå Žåãåºåã¯çæ³çã«ã¯LOã®äžåŽã ãã«çŸããŸããäžæ¹ãQãã£ã³ãã«ã®ä¿¡å·ãIãã£ã³ãã«ã®ä¿¡å·ãã90°é²ãã§ããå Žåã«ã¯ãåºåã¯LOã®äžåŽã ãã«çŸããŸããããã§ãç¬ç«ãã2ã€ã®ããŒã¹ãã³ãä¿¡å·ãçæãã1ã€ã¯ãµã€ããã³ãã®äžåŽã®ã¿ã«åºåããããã«ããã1ã€ã¯ãµã€ããã³ãã®äžåŽã®ã¿ã«åºåããããã«èšèšãããšããŸãããã®å Žåã2ã€ã®ä¿¡å·ã¯ããŒã¹ãã³ãé åã§å ç®ãããè€çŽ ãã©ã³ã¹ããã¿ã«éãããŸãããã®çµæãåºåã«ã¯ãLOã®äžäžã«ç°ãªãä¿¡å·ãçŸããŸããå®éã®ã¢ããªã±ãŒã·ã§ã³ã§ã¯ãçµåãããããŒã¹ãã³ãä¿¡å·ãããžã¿ã«çã«çæãããŸãããªããå³7ã®å ç®ããŒãã¯ãã®ãããªæŠå¿µã瀺ãããã«æãããã®ã§ãã

ãŒãIFãããããã¡ãªãã
äžèšã®ããã«ããããšã§ãè€çŽ ãã©ã³ã¹ããã¿ã䜿çšããŠåäžã®ãµã€ããã³ãåºåãçæããããšãã§ããŸãããã®æ¹æ³ãæ¡çšããã°ãRFãã£ã«ã¿ã«ããã€ã¡ãŒãžã®é€å»ã®é¢ã§å€§ããªã¡ãªãããåŸãããŸããããããç¡èŠã§ããã¬ãã«ãŸã§ã€ã¡ãŒãžãäœæžå¯èœãªé€å»æ§èœãããã°ããŒãIFã¢ãŒããã¯ãã£ããã£ãšå¹æçã«å©çšã§ããŸãããŒãIFã¢ãŒããã¯ãã£ã§ã¯ãç¹å¥ã«çæããããŒã¹ãã³ãã»ããŒã¿ã䜿çšããããšã«ãããLOã®çåŽã«ç¬ç«ããä¿¡å·ãçŸããRFåºåãçæããããšãå¯èœã«ãªããŸããå³8ã¯ããã®å ·äœçãªæ¹æ³ã瀺ãããã®ã§ããããã§ã¯2çµã®I/Qãã£ã³ãã«ã®ããŒã¿ãããããããããäºãã«ç¬ç«ããŠãããã®ãšããŸããã¬ã·ãŒãã§ã¯ããããããªãã¡ã¬ã³ã¹ã»ãã£ãªã¢ã®äœçžã«å¯ŸããŠãã³ãŒããå¯èœãªã·ã³ãã«ã»ããŒã¿ãšããŠãšã³ã³ãŒããããŸãã

æåã®æ³¢åœ¢ã§ã¯ãQ1ã¯I1ãã90°äœçžãé²ãã§ãããæ¯å¹ ã¯åãã§ããããšãããããŸããåæ§ã«ãI2ã¯Q2ãã90°é²ãã§ãããæ¯å¹ ã¯åãã§ããããã§I1+I2=SumI1I2ãQ1+Q2=SumQ1Q2ãšãªãããã«ã2ã€ã®ç¬ç«ããä¿¡å·ãçµåããŸããå ç®ãããI/Qã®ä¿¡å·ã«ã¯ãäœçžãæ¯å¹ ã®çžé¢é¢ä¿ã¯ãããŸãããæ¯å¹ ã¯åžžã«çããããã§ã¯ãªããäœçžé¢ä¿ãå€åããŸãããããµãŒããã®åºåãšããŠã¯ãå³7ã«ç€ºããããã«ãI1/Q1ã®ããŒã¿ããã£ãªã¢ã®çåŽã«ãI2/Q2ã®ããŒã¿ããã£ãªã¢ã®ããäžæ¹ã®åŽã«çŸããŸãã
ãŒãIFã¢ãŒããã¯ãã£ã§ã¯ãç¬ç«ããããŒã¿ã»ãããã¯ãLOã®äž¡åŽã«é£æ¥ããŠé 眮ãããããšãããè€çŽ ãã©ã³ã¹ããã¿ã®ã¡ãªããã¯ããã«åŒ·åãããŸããããŒã¿åŠçãè¡ããã¹ã®åž¯åå¹ ã¯ãRFããŒã¿ã®åž¯åå¹ ãè¶ ããããšã¯ãããŸããããã®ãããçè«çã«ã¯ãŒãIFã¢ãŒããã¯ãã£ã§äœ¿çšãããè€çŽ ãããµãŒã«ãã£ãŠããŒã¹ãã³ãã®ãã¯ãŒå¹çãæé©åãããŸããåæã«ãRFãã£ã«ã¿ã«ããåŠçãå¿ èŠãšããªããœãªã¥ãŒã·ã§ã³ãåŸãããæªäœ¿çšã®ä¿¡å·åž¯åå¹ ã«ãããåäœåœããã®ã³ã¹ããäœæžããããšãå¯èœã«ãªããŸãã
ãããŸã§ã¯ããŒãIFãã©ã³ã¹ããã¿ãå®çŸããè€çŽ ãããµãŒã«æ³šç®ããŠè©±ãé²ããŠããŸãããåãåçãéã«äœçšãããã°ãè€çŽ ãããµãŒã®ã¢ãŒããã¯ãã£ããŒãIFã¬ã·ãŒããšããŠäœ¿çšã§ããŸãããã©ã³ã¹ããã¿ã«ã€ããŠè¿°ã¹ãŠããå©ç¹ã¯ãã¬ã·ãŒãã«ãåãããã«åœãŠã¯ãŸããŸããåäžã®ãããµãŒã䜿çšããŠä¿¡å·ãåä¿¡ããå Žåãã€ã¡ãŒãžã¯RFãã£ã«ã¿ã«ãã£ãŠæåã«é€å»ããå¿ èŠããããŸãããŒãIFã®ã·ã¹ãã ãšããŠæ©èœãããå Žåãæ³šæãå¿ èŠãªã€ã¡ãŒãžåšæ³¢æ°ãšãããã®ã¯ãªããLOã®äžåŽã®ä¿¡å·ã¯LOã®äžåŽã®ä¿¡å·ãšã¯ç¬ç«ããŠåä¿¡ãããŸãã
å³9ã«è€çŽ ã¬ã·ãŒãã®æŠèŠã瀺ããŸãããIãã£ã³ãã«ãšQãã£ã³ãã«ã®ãããµãŒã«ã¯å ¥åä¿¡å·ãäžããããŸããäžæ¹ã®ãããµãŒã¯LOã§é§åãããããäžæ¹ã¯LOãšã¯90°ç°ãªãäœçžã§é§åãããŸããã¬ã·ãŒãã¯Iãã£ã³ãã«/Qãã£ã³ãã«ã®ä¿¡å·ãåºåããŸãã
ã¬ã·ãŒãã®å Žåãäžããããå ¥åã«å¯Ÿããåºåãå®éšçã«ç¢ºèªããã®ã¯å®¹æã§ã¯ãããŸããããã ãå ¥åãšãªãããŒã³ã®åšæ³¢æ°ãLOããé«ãå Žåãå³ã«ç€ºãããã«ãI/Qãã£ã³ãã«ã®åºååšæ³¢æ°ã¯ïŒ»ããŒã³-LOã«ãªããŸãããŸããQãã£ã³ãã«ã¯Iãã£ã³ãã«ãããäœçžãé ãããšäºæž¬ã§ããŸããåæ§ã«ãå ¥åãšãªãããŒã³ã®åšæ³¢æ°ãLOããäœãå Žåã«ã¯ãI/Qãã£ã³ãã«ã®åºååšæ³¢æ°ã¯ïŒ»LO-ããŒã³ïŒœã«ãªããŸãããã®éãQãã£ã³ãã«ã®äœçžã¯Iãã£ã³ãã«ãããé²ãã§ããã¯ãã§ãããã®ããã«ããããšã§ãè€çŽ ã¬ã·ãŒãã§ã¯LOããäžåŽã®ãšãã«ã®ãŒãšLOããäžåŽã®ãšãã«ã®ãŒãåé¢ããããšãã§ããŸããè€çŽ ã¬ã·ãŒãã®åºåã¯ãLOããäžåŽã®åä¿¡ã¹ãã¯ãã«ã§è¡šãããI/Qãã£ã³ãã«ã®æ å ±ãšãLOããäžåŽã®åä¿¡ã¹ãã¯ãã«ã§è¡šãããI/Qãã£ã³ãã«ã®æ å ±ã®åã«ãªããŸããããã¯ãè€çŽ ãã©ã³ã¹ããã¿ã«ã€ããŠèª¬æããæŠå¿µãšåãã§ããè€çŽ ãã©ã³ã¹ããã¿ã«ã¯ãIãã£ã³ãã«ã®ä¿¡å·ã®åãšQãã£ã³ãã«ã®ä¿¡å·ã®åãéãããŸããããã«å¯Ÿããè€çŽ ã¬ã·ãŒãã§ã¯ãIãã£ã³ãã«ã®ä¿¡å·ã®åãšQãã£ã³ãã«ã®ä¿¡å·ã®åããããã®æ å ±ãããŒã¹ãã³ãã»ããã»ããµã«å ¥åãããŸããåããã»ããµã§è€çŽ FFTïŒé«éããŒãªãšå€æïŒã宿œããããšã«ãããäžåŽã®åšæ³¢æ°ãšäžåŽã®åšæ³¢æ°ã«å®¹æã«åé¢ããããšãã§ããŸãã

å ç®ãããIãã£ã³ãã«ã®ä¿¡å·ãšå ç®ãããQãã£ã³ãã«ã®ä¿¡å·ã¯æ¢ç¥ã®ä¿¡å·ã§ãããã ãI1ãQ1ãI2ãQ2ã®4ã€ã¯æªç¥ã®ä¿¡å·ã§ããæ¢ç¥ã®ä¿¡å·ããæªç¥ã®ä¿¡å·ã®æ¹ãå€ãã®ã§ãI1ãQ1ãI2ãQ2ã¯æ±ããããªãããã«æãããããããŸãããããããå®éã«ã¯I1=Q1+90°ãI2=Q2-90°ã§ããããšã¯ããã£ãŠããŸãããã®ãããããã2ã€ã®åŒãå ããã°ãI1ãQ1ãI2ãQ2ãæ±ããããšãã§ããŸãããããããQãã£ã³ãã«ã®ä¿¡å·ã¯Iãã£ã³ãã«ã®ä¿¡å·ã®äœçžã±90°ã·ããããŠã³ããŒãããã®ã§ãããããã£ãŠãå®éã«æ±ããå¿ èŠãããã®ã¯I1ãšI2ã ãã§ãã
å¶çŽ
çŸå®ã®è€çŽ ãããµãŒã§ã¯ãã€ã¡ãŒãžä¿¡å·ãå®å šã«é€å»ããŠé«ãæ§èœãåŸãã®ã¯ç°¡åãªããšã§ã¯ãããŸããããã®åå ãšãªãå¶çŽã¯ãç¡ç·ã¢ãŒããã¯ãã£ã®èšèšã«ãããŠ2ã€ã®æç¢ºãªåœ±é¿ãåãŒããšèããããšãã§ããŸãã
æ§èœã®é¢ã§å¶çŽããããšããŠããè€çŽ IFãæ¡çšããã°æãããªã¡ãªãããåŸãããŸããå³10ã«ç€ºãããããªäœãIFã䜿çšããäŸãèããŠã¿ãŸããããä»®ã«æ§èœäžã®å¶çŽã蚱容ãããšãããšãã€ã¡ãŒãžãçŸããŸãããããããã®ã€ã¡ãŒãžã¯ãåäžã®ãããµãŒã䜿çšããèšèšïŒ å³6 ïŒã§äºæ³ãããã€ã¡ãŒãžãããå€§å¹ ã«æžè¡°ããŠããŸããè€çŽ ãããµãŒã§ã¯ãã®éšåã«ãã£ã«ã¿ãå¿ èŠã«ãªããŸãããããããã®ãã£ã«ã¿ã«å¯ŸããèŠä»¶ã¯ããªãç·©ãããªã®ã§å®¹æãã€äœã³ã¹ãã§å®çŸã§ããŸãã

ãã£ã«ã¿ã®è€éãã¯ãã€ã¡ãŒãžãšææã®ä¿¡å·ã®éã®è·é¢ã«åæ¯äŸããŸãããŒãIFã®æ§æãæ¡çšããå Žåãè·é¢ã¯ãŒãã«ãªããŸããã€ãŸããã€ã¡ãŒãžã¯ææã®ä¿¡å·åž¯åå ã«çŸããŸãããŒãIFã®çè«ãçŸå®ã®ã¢ããªã±ãŒã·ã§ã³ã«é©çšããã«ã¯ããªãã®èŠåŽã䌎ããŸãã垯åå ã®ã€ã¡ãŒãžã蚱容å¯èœãªã¬ãã«ãè¶ ãããšæ§èœãäœäžããŸãïŒå³11ïŒã

è€çŽ ãã©ã³ã¹ããã¿/ã¬ã·ãŒãã®åçã¯ãI /Qã®ããŒã¿ã»ãã¹ã«ãããäœçžãšæ¯å¹ ã®èŠä»¶ãæºããããŠããæã ãæãç«ã¡ãŸããä¿¡å·ãã¹ã®äžæŽåã¯ãLOã®äž¡åŽã«ãããŠã€ã¡ãŒãžãäœã粟床ã§ããé€å»ã§ããªããšããçµæã«ã€ãªãããŸãããã®ãããªåé¡ã«ã€ããŠã¯å³10ãšå³11ã«ãã£ãŠç¢ºèªããããšãã§ããŸãããŒãIFãæ¡çšããŠããªãå Žåãã€ã¡ãŒãžãé€å»ããããã«æãããã£ã«ã¿ã䜿çšããããšã«ãªãã§ããããäžæ¹ããŒãIFãæ¡çšããŠããå Žåã«ã¯ãäžèŠãªã€ã¡ãŒãžãææã®ä¿¡å·åž¯åå ã«çŸããŸãããã®ãã¯ãŒã倧ãããããšãäœããã®äžå ·åãçããããšã«ãªããŸãããŒãIFãšè€çŽ ãããµãŒãçµã¿åãããããšã§ãã·ã¹ãã èšèšã«å¯ŸããŠå€§ããªã¡ãªãããæäŸãããœãªã¥ãŒã·ã§ã³ãå®çŸããããšãã§ããŸãããã ããããã¯èšèšã«ãã£ãŠä¿¡å·ãã¹ã®äœçžãšæ¯å¹ ã®äžæŽåãé€å»ã§ããå Žåã«éããããšããããšã§ãã
å é²çãªã¢ã«ãŽãªãºã ã®å®çŸ
è€çŽ ãããµãŒã䜿çšããã¢ãŒããã¯ãã£ã®ã³ã³ã»ããã¯äœå¹ŽãåããååšããŠããŸããããã ããã€ãããã¯ãªç¡ç·ç°å¢ã«ãããŠäœçžãšæ¯å¹ ã®èŠä»¶ãæºãããªããã°ãªããªããšãã課é¡ãããŒãIFã¢ãŒãã®æ®åã劚ããèŠå ãšãªã£ãŠããŸãããã¢ããã°ã»ããã€ã»ãºã¯ãé«åºŠãªICèšèšãšå é²çãªã¢ã«ãŽãªãºã ãçµã¿åãããããšã«ããããã®èª²é¡ãå æããŸãããä¿¡å·ãã¹ã«ååšããåé¡ã¯ãé«åºŠãªICèšèšã«ããæå°åããããããããçšåºŠã®é害ã蚱容ã§ããŸãããŸãããã®ä»ã®äžå®å šãªéšåã«ã€ããŠã¯ãQECïŒQuadrature Error CorrectionïŒã®ã¢ã«ãŽãªãºã ãèªå·±æé©åããããšã«ãã£ãŠæ ¡æ£ããããšãã§ããŸãïŒå³12ïŒã

ãAD9371ãã«ä»£è¡šãããã¢ããã°ã»ããã€ã»ãºã®ãã©ã³ã·ãŒãICã§ã¯ãå èµããARMããã»ããµã«ãã£ãŠQECã®ã¢ã«ãŽãªãºã ãå®è¡ãããŸãããã®ã¢ã«ãŽãªãºã ã«ã¯ãICã®ä¿¡å·ãã¹ãå€èª¿ãããRFåºåãå ¥åä¿¡å·ã«é¢ããæ å ±ïŒKnowledgeïŒãçã蟌ãŸããŸããããã«ãããåã©ããã®åŠçãè¡ãã®ã§ã¯ãªããäºæž¬å¶åŸ¡çãªæ¹æ³ã«ãã£ãŠä¿¡å·ãã¹ã®ãããã¡ã€ã«ãç¥çïŒIntelligentïŒã«é©å¿ãããŸãããã®ã¢ã«ãŽãªãºã ã¯ãã¢ããã°ä¿¡å·ãã¹ã®æ§èœãããžã¿ã«çãªã¢ã·ã¹ãã«ãã£ãŠåäžããããã®ã ãšèšãããšãã§ããŸãã
QECã®ã¢ã«ãŽãªãºã ã䜿çšãããã€ãããã¯ãªãã£ãªãã¬ãŒã·ã§ã³ã¯ãåªããæ©èœã§ããããããããã¯ã¢ããã°ã»ããã€ã»ãºã®ãã©ã³ã·ãŒãICãåããå é²çãªã¢ã«ãŽãªãºã ã®äžäŸã«ãããŸãããäŸãã°ãLOãªãŒã¯ãé€å»ããæ©èœãªã©ãããŒãIFã¢ãŒããã¯ãã£ãæé©ãªã¬ãã«ã®æ§èœã«åŒãäžããããšã«è²¢ç®ããŸãããããã第1äžä»£ã®ã¢ã«ãŽãªãºã ã¯ãäž»ã«ãã©ã³ã·ãŒãæè¡ã®å®çŸã®ããã«å¿ èŠã«ãªã£ããã®ã§ããäžæ¹ãããžã¿ã«ã»ããªãã£ã¹ããŒã·ã§ã³ïŒDPDïŒãã¯ãããšãã第2äžä»£ã®ã¢ã«ãŽãªãºã ã¯ããã©ã³ã·ãŒãã ãã§ãªãã·ã¹ãã å šäœã®æ§èœãåäžãã圹å²ãæãããŸãã
ããããã·ã¹ãã ã¯å®å šãªãã®ã§ã¯ãããŸããããã®ãããæ§èœã¯å¶éãããŸãã第1äžä»£ã®ã¢ã«ãŽãªãºã ã¯ãäž»ã«ãã©ã³ã·ãŒãå éšã®å¶çŽãæ ¡æ£ããããšã«éç¹ã眮ãããã®ã§ãããããã«å¯Ÿãã第2äžä»£ã®ã¢ã«ãŽãªãºã ã¯ãããç¥çãªåŠçãè¡ãããšã§ãã·ã¹ãã ã®æ§èœãšå¹çã«åœ±é¿ãåãŒããã©ã³ã·ãŒãå€éšã®å¶çŽãè£åããŸããäŸãã°ãPAã®æªã¿/å¹çïŒDPD/CFRïŒããã¥ãã¬ã¯ãµã®æ§èœïŒTxNcïŒãçžäºå€èª¿æªã¿ïŒPIMïŒã®åé¡ãªã©ã®è§£æ¶ã«åœ¹ç«ã¡ãŸãã
ãŸãšã
è€çŽ ãããµãŒã¯ããªã以åããååšããæè¡ã§ãããããããã®ã€ã¡ãŒãžé€å»æ§èœã¯ããŒãIFã®æ§æã§äœ¿çšã§ããã»ã©ã®ã¬ãã«ã«ã¯éããŠããŸããã§ããããããã髿§èœã®ã·ã¹ãã ã«ãããŠãŒãIFã¢ãŒããã¯ãã£ã®æ¡çšã劚ããŠããæ§èœé¢ã®éå£ã¯ãé«åºŠãªICèšèšãšå é²çãªã¢ã«ãŽãªãºã ãçµã¿åãããããšã«ãã£ãŠåãæãããŸãããæ§èœé¢ã®å¶çŽãæé€ãããããšããããŒãIFã¢ãŒããã¯ãã£ãå®çšçã«äœ¿çšããããšãå¯èœã«ãªããŸããããã®çµæããã£ã«ã¿åŠçããã¯ãŒãã·ã¹ãã ã®è€éãããµã€ãºãç±ãééã«é¢ããåé¡ã軜æžãããŸããïŒããã«ã€ããŠã¯ãBrad Brannonãå·çããèšäºãã芧ãã ãã1ïŒã
è€çŽ ãããµãŒãšãŒãIFã䜿çšããå ŽåãQECã®ã¢ã«ãŽãªãºã ãšLOãªãŒã¯ã®åœ±é¿ãåæžããããã®ã¢ã«ãŽãªãºã ãçŸå®çãªæ©èœã«ãªããŸããããããã¢ã«ãŽãªãºã éçºã®ç¯å²ã¯æ¡å€§ããŠãããã·ã¹ãã èšèšè ã«æäŸãããæ§èœã¯ãç¡ç·èšèšãããã«æè»ã«è¡ããã¬ãã«ãŸã§åäžããŠããŸããèšèšè ã¯ãç¡ç·èšèšã«ãããŠããé«ãæ§èœãåŸãããããã«ãããŸããŸãªéžæãè¡ãã¯ãã§ãããŸããããã ãã§ãªããäœã³ã¹ãã§å°åã®ã³ã³ããŒãã³ãã䜿ããããã«ããããã«ãã¢ã«ãŽãªãºã ã«ãã£ãŠåŸãããã¡ãªãããæŽ»çšããã±ãŒã¹ããããããããŸããã