Jagadeesh Harshan

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— The capacity region of a two-user Gaussian Multiple Access Channel (GMAC) with complex finite input alphabets and continuous output alphabet is studied. When both the users are equipped with the same code alphabet, it is shown that, rotation of one of the user's alphabets by an appropriate angle can make the new pair of alphabets not only uniquely(More)
Distributed Orthogonal Space-Time Block Codes (DOSTBCs) achieving full diversity order and single-symbol ML decodability have been introduced recently by Yi and Kim for cooperative networks and an upperbound on the maximal rate of such codes along with code constructions has been presented. In this paper, we introduce a new class of Distributed STBCs called(More)
— Constellation Constrained (CC) capacity regions of a two-user Gaussian Multiple Access Channel (GMAC) have been recently reported. For such a channel, code pairs based on trellis coded modulation are proposed in this paper with M-PSK and M-PAM alphabet pairs, for arbitrary values of M, to achieve sum rates close to the CC sum capacity of the GMAC. In(More)
— Distributed space time coding for wireless relay networks where the source, the destination and the relays have multiple antennas have been studied by Jing and Hassibi. In this set up, the transmit and the receive signals at different antennas of the same relay are processed and designed independently, even though the antennas are colocated. In this(More)
— Constellation Constrained (CC) capacity regions of a two-user SISO Gaussian Multiple Access Channel (GMAC) with finite complex input alphabets and continuous output are computed in this paper. When both the users employ the same code alphabet, it is well known that an appropriate rotation between the alphabets provides unique decodability to the receiver.(More)
fading MAC such that the sphere decoding complexity is reduced. I. INTRODUCTION AND PRELIMINARIES Capacity regions of two-user Gaussian Multiple Access Channels (GMAC) (shown in Fig.1) are well known in the literature wherein the capacity achieving input is continuous and Gaussian distributed [1]-[5]. Though, capacity regions of such channels provide(More)
— Distributed Space-Time Block Codes (DSTBCs) from Complex Orthogonal Designs (CODs) (both square and non-square CODs other than the Alamouti design) are known to lose their single-symbol ML decodable (SSD) property when used in two-hop wireless relay networks using amplify and forward protocol. For such a network, in this paper, a new class of high rate,(More)
Distributed Orthogonal Space-Time Block Codes (DOSTBCs) achieving full diversity order and single-symbol ML decodability have been introduced recently for cooperative networks and an upper-bound on the maximal rate of such codes along with code constructions has been presented. In this report, we introduce a new class of Distributed STBCs called(More)
— Recently, the idea of space-time coding has been applied to wireless relay networks wherein a set of geographically separated relay nodes cooperate to process the received signal from the source and forward them to the destination such that the signal received at the destination appears like a Space-Time Block Code (STBC). Such STBCs (referred to as(More)