Packet Access For Cellular Systems: The Capacity Of S-Aloha And Cdpa With Slow Shadowing

The paper discusses the features and compares the performance of two packet oriented channel-access schemes that appear particularly suitable for the PCN cellular environment. These schemes exploit the packet capture and can deal with inter-cell interference without any a priori bandwidth-consuming techniques such as those used in FDMA and CDMA. The first scheme is the well knownS-ALOHA, whereas the secondone is the Capture Division Packetized Access, recently proposed. The analytical model accounts for several features of real-world systems, e.g., the exact traffic pattern that must be offered in order to achievethroughput fairness, the exact interference caused by the traffic in the same cell and in other cells, the fading, the slow shadowing attenuation and some means to counteract it, such as best base station selection and power control. We also discuss the effects of outage, i.e., a mechanism which prevents a user from attempting more than a predetermined number of transmissions ..