pSIC Perfect Successive Interference Cancelation

Perfect Successive Interference Cancellation (pSIC) is a technique used in wireless communication systems to mitigate interference and improve the overall performance of the system. It is particularly effective in scenarios where there are multiple users transmitting signals simultaneously and causing interference to each other.

In wireless communication, interference occurs when multiple signals occupy the same frequency spectrum and overlap in time. This interference can degrade the quality of received signals, resulting in a decrease in communication reliability and data rates. Interference cancellation techniques aim to mitigate the effects of interference by removing or reducing its impact on the desired signal.

pSIC is a multi-user interference cancellation technique that works by iteratively canceling the interference from multiple interfering signals. It is called "successive" interference cancellation because it cancels the interference from each signal one after the other in a specific order.

The basic principle of pSIC involves decoding the strongest interfering signal first and subtracting its estimated contribution from the received signal. By removing the strongest interference, the receiver can then focus on decoding the next strongest interfering signal, and so on. This process continues until all the interfering signals are canceled or their impact is reduced to an acceptable level.

To implement pSIC, the receiver needs to have knowledge about the interfering signals, including their timing, power levels, and modulation schemes. This information can be obtained through various means, such as cooperative signaling between users or advanced signal processing techniques.

The pSIC algorithm typically follows these steps:

1. Signal Detection: The receiver detects and identifies the presence of multiple interfering signals in the received signal.
2. Interference Cancellation: The receiver selects the strongest interfering signal and estimates its contribution to the received signal. It then subtracts this estimated interference from the received signal.
3. Signal Decoding: The receiver attempts to decode the desired signal from the interference-cancelled signal. It uses decoding algorithms tailored to the modulation scheme and coding scheme employed by the desired signal.
4. Iteration: If there are remaining interfering signals after the first iteration, the receiver repeats steps 2 and 3 for the next strongest interfering signal. This process continues until all the interfering signals are canceled or their impact is sufficiently reduced.

pSIC offers several advantages over other interference cancellation techniques. It is relatively simple to implement and does not require complex channel estimation or joint decoding of multiple signals. Additionally, pSIC can achieve significant interference cancellation gains in scenarios with strong interfering signals.

However, pSIC also has some limitations. It assumes that the receiver has accurate knowledge of the interfering signals, which may not always be available. Moreover, pSIC is susceptible to error propagation, where errors made during interference cancellation can affect the decoding of subsequent signals.

In conclusion, Perfect Successive Interference Cancellation (pSIC) is a technique used in wireless communication systems to cancel interference from multiple simultaneous signals. By iteratively canceling the interference from the strongest interfering signals, pSIC improves the overall performance of the system and enhances the reliability of communication.