Authenticating Requests: Using the Authorization Header (AWS Signature Version 4)
Using the HTTP Authorization header is the most common method of providing authentication information. Except for POST requests and requests that are signed by using query parameters, all Amazon S3 operations use the Authorization request header to provide authentication information. The following is an example of the Authorization header value.
https://docs.aws.amazon.com/AmazonS3/latest/API/sigv4-auth-using-authorization-header.html