Permission-based multiple access communications systems

A communication system configured for selectively controlling access to multiple data streams which are communicated using a shared frequency spectrum and shared spreading codes, comprising:

• a first discrete time amplitude modulator generating a first product signal by spreading first symbols of a first amplitude modulated signal using a first spreading code;
• a second discrete time amplitude modulator configured for generating a second product signal by spreading second symbols of a complimentary amplitude modulated signal using a second spreading code;
• a first combiner configured for combining said first and second product signals to form a protected data communication signal including first data recoverable by at least one receiver of a plurality of receivers;
• and
• a second combiner configured for combining a global data communication signal and said protected data communication signal to form an output signal having a spread spectrum format;
• wherein said global data communication signal is generated using a digital modulation process and includes second data recoverable by all of said plurality of receivers.