Spatial Modulation

Spatial modulation is a radically new wireless transmission technique that combines digital data modulation and multiple antenna transmission in a novel fashion. The key invention is a three dimensional data constellation diagram which hosts the entire alphabet of possible symbols to be transmitted. The additional dimension creates the necessary space to fit in more symbols effectively enlarging the alphabet. This directly translates into higher data rate without the need for additional radio frequency spectrum. Key properties of spatial modulation are: (1) It requires only a single radio frequency (RF) chain, regardless of the number of antennas used; (2) low complexity algorithms can be deployed at the receiver to decode the transmitted information. This results in a spectrum efficient and energy efficient novel transmission scheme suitable for future wireless communications.

- Spatial modulation significantly enhances the performance of wireless communications systems. In particular, it strikes a unique trade-off between spectrum efficiency (the number of bits transmitted per Hertz bandwidth), energy efficiency and implementation complexity. The data rate increases with the number of antennas while the energy consumptions remains largely constant. It is therefore a strong candidate for next generation wireless communications standards that strive for orders of magnitude improved energy efficiency and spectrum efficiency.
- Spatial modulation enables optical wireless communication systems composed of inexpensive off-the-shelf light emitting diodes (LEDs) to achieve data rates in the region of hundreds of mega bits per second (Mbps). This is achieved at low implementation complexity rendering spatial modulation a practical technique for emerging terrestrial optical wireless communications.
- Spatial modulation not only is a technique that improves the performance of a wireless communication link, but it also has demonstrated significant performance gains when used for wireless relaying systems and deployment scenarios that involve multiple terminals.
- It has also been demonstrated that spatial modulation can be used to enhance the robustness of a wireless communications link against eavesdroppers.