运用matlab,采用QPSK调制与解调，包括串并转换，傅立叶变换与逆变换，信道估计（采用LS准则），多普勒频移等模块，内容清晰明了。-Use matlab, using QPSK modulation and demodulation, including string and conversion, Fourier Transform and inverse transform, channel estimation (LS criteria used), Doppler frequency shift modules, content clarity.
SHOW FULL COLUMNS FROM `jrk_downrecords` [ RunTime:0.000981s ]
SELECT `a`.`aid`,`a`.`title`,`a`.`create_time`,`m`.`username` FROM `jrk_downrecords` `a` INNER JOIN `jrk_member` `m` ON `a`.`uid`=`m`.`id` WHERE `a`.`status` = 1 GROUP BY `a`.`aid` ORDER BY `a`.`create_time` DESC LIMIT 10 [ RunTime:0.083704s ]
SHOW FULL COLUMNS FROM `jrk_tagrecords` [ RunTime:0.000994s ]
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SHOW FULL COLUMNS FROM `jrk_member` [ RunTime:0.000949s ]
SELECT `id`,`username`,`userhead`,`usertime` FROM `jrk_member` WHERE `status` = 1 ORDER BY `usertime` DESC LIMIT 10 [ RunTime:0.003080s ]
SHOW FULL COLUMNS FROM `jrk_searchrecords` [ RunTime:0.000825s ]
SELECT * FROM `jrk_searchrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 5 [ RunTime:0.003633s ]
SELECT aid,title,count(aid) as c FROM `jrk_downrecords` GROUP BY `aid` ORDER BY `c` DESC LIMIT 10 [ RunTime:0.024250s ]
SHOW FULL COLUMNS FROM `jrk_articles` [ RunTime:0.001630s ]
UPDATE `jrk_articles` SET `hits` = 2 WHERE `id` = 32534 [ RunTime:0.012391s ]
