What is a characteristic of signals transmitted by satellites using CDMA?

The characteristic of signals transmitted by satellites using Code Division Multiple Access (CDMA) is that signals are separated into distinct channels using unique codes. This method allows multiple users to transmit simultaneously over the same frequency band without interference. Each user's signal is encoded with a specific code that acts like a unique identifier, enabling the receiver to distinguish between signals from various users even when they are transmitted at the same time.

In contrast, the other options do not accurately describe CDMA. While it is true that satellites may operate on different frequencies, this is not a defining feature of CDMA. Moreover, user location is indeed relevant in certain satellite applications, particularly for positioning services. Finally, the assertion that all satellites transmit signals simultaneously without separation does not align with the fundamental principles of CDMA, where signals must be uniquely coded to maintain clarity in communication.