BEAM-PATTERN-SCANNING DYNAMIC-TIME BLOCK CODING

In this paper we introduce a novel transmit diversity where the space diversity in space-time block codes (STBC) is replaced by Beam Pattern Scanning (BPS). In BPS technique carefully controlled time varying phase shifts are applied to the antenna array elements mounted at the base station creating small movement in the beam pattern directed toward the desired users. In dense environments, this small movement of the antenna beam pattern creates an artificial fast fading channel leads to time diversity exploitable at the receiver. A new time dependent block coding is introduced to compensate the effect of time-varying phase shifts and ease the process of reception. Hence, we call this technique BPS/Dynamic-time block coding (BPS/DTBC). Through this merger, we achieve: 1) directionality, which supports Space Division Multiple Access (SDMA); and 2) high order of time diversity gains, which lead to a high performance. In this paper, we discuss the structure of base station antenna arrays and receiver, and we generate the probability-of-error performance simulations. These simulations show a high probability-of-error performance is achievable through the employment of BPS/DTBC scheme, compared with traditional space-time block coding. Index Terms – beam pattern scanning, transmit diversity, space-time block codes, dynamic-time block codes