To connect at 450Mbps you must have a compatible and properly configured 450Mbps access point to connect to. For example, TRENDnet carries the following.

450Mbps wireless Router with access point: TEW-691GR.
https://www.TRENDnet.com/products/product-detail.asp?prod=215_TEW-691GR

450Mbps wireless access point: TEW-690AP
https://www.TRENDnet.com/products/product-detail.asp?prod=100_TEW-690AP

To achieve 450Mbps you must be using WPA2 AES encryption values and have set the channel bandwidth to Auto 20/40MHz.