Dynamic fractional signature sequence reuse (DFSSR) scheme for CDMA system

Inter-cell interference management is an notorious issue in cellular communication. Traditionally, static techniques were used to manage the interference: frequency reuse for GSM or universal reuse for CDMA. More recently, fractional frequency reuse for LTE has been common. Based on this idea, the next set of ideas consider coordination among base stations to dynamically manage the interference among the cells. Typically this is done in the context of OFDM systems (LTE), and in particular distributed antenna system (DAS) for LTE (coordinated beamforming). In this paper, the implications of this approach in CDMA systems (example: HSPA+) are discussed. The key idea is that it is not just important to reduce total inter-cell interference, but also the dimension (measured in chips over a spreading sequence length - 16 chips in HSPA) over which the interference is caused. This leads to novel interference management techniques that are specific to CDMA technology, which we term dynamic fractional signature sequence reuse (DFSSR).