In chapter 5, demodulation models of many modulation systems are established. Squareloop model is established to detect carrier.
第五章中给出了对各种调制方式的解调模型，成功建立了平方环载波恢复模型。
2
Looking from a distance like a gigantic arch, it is a continuous loop, a kind of square doughnut.
从远处看像一座巨大的拱门，它是一个连续的环，像一种方形面包圈。
3
(youtube.com/user/dabblerDOTca) has instructional videos on how to tie a tie, fold a pocket square, sniff out a good wine and perfect a loop choke self-defence manoeuvre.