一直以來也沒搞清楚USB 3.2的10Gbps的形式，一直以爲是5Gbps*2lane。
翻看了下USB 3.2的協議，終於搞明白了。協議上是這麼說的：
3.2.1 Physical Layer
The Gen X physical layer specifications are detailed in Chapter 6. The physical layer defines the PHY portion of a port and physical connection between a downstream facing port（on a host or hub）and the upstream facing port on a device. The Gen X physical connection is comprised of two differential data pairs(one transmit pat and one receive path) for each lane. Dual-lane support(Gen X x 2) is defined to enable two lane operation over the USB Type-C cable and connector.
傳輸速率分爲Gen 1（5Gbps）和Gen 2（10Gbps），在Type-C接口上可以實現2lane同時傳輸，即Gen 1 x 2（10Gbps）和Gen 2 x 2（20Gbps）。
USB 3.2協議連接如下：
https://usb.org/document-library/usb-32-specification-released-september-22-2017-and-ecns