Frequency Reuse
The 3GPP UMTS TD-CDMA standard is inherently designed to support n=1 reuse (single frequency network), the reason being that operators in the IMT 2000 3G band are only allocated a single TDD channel.

To be able to support true n=1 reuse, a technology must be able to operate with negative C/I (wanted signal below the level of interference / noise). UMTS TD-CDMA achieves this by using direct-sequence spread-spectrum, which provides the processing gain required for negative C/I operation.

IPWireless can therefore operate with all cells and sectors on the same frequency. In areas on cell overlap, UE continue to operate down to approximately -10 dB C/I.

The UMTS TD-CDMA system adapts dynamically to channel conditions, including C/I that is the dominant factor in the throughput achieved in an interference-limited environment. Therefore, while the system operates perfectly with n=1 reuse, average UE throughputs will be significantly higher if a multiple-frequency reuse is use. A reuse of n=3 with 3-sector sites (1:3 reuse) is commonly used by operators who have sufficient spectrum. Other reuse schemes are also feasible, such as n=2 with 4 sector sites (1:2 reuse. Simulations and trial results show that there is little advantage in reuse greater than n=3, as n=3 performance is similar to the "no interference" case.