New simple cooperative relaying schemes

In this paper we propose new schemes for increasing code rate of simple cooperative relaying with virtual orthogonal space time block coding (OSTBC). The proposed schemes are used for creating virtual 4×1 multiple input-single output channel (MISO). These systems include one base station (BS) with two antennas, two relay stations (RS) each with a single antenna and one mobile station (MS) with a single antenna. One of the main disadvantages of the virtual OSTBC is its code rate, so we propose new simple cooperative relaying schemes with greater code rate while preserving BER of the scheme with virtual OSTBC. We proposed new schemes with greater code rate on the first hop while the code rate on the second hop remains the same. The code rates between BS and RSs in the proposed schemes are 1, 4/5, 2/3 and 4/7, while in the scheme with virtual OSTBC the code rate is only 1/2. The simulation results show that the proposed schemes maintain BER performance very close to the scheme with virtual OSTBC.