Conference Paper

YMMV: Multiple Session Multicast with MIMO

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Abstract

Multicast is an important application in cellular networks. The 4G technologies, including WiMAX and LTE, invariably adopt Multiple- Input-Multiple-Output (MIMO) to facilitate spatial multiplexing and fundamentally increase channel capacity. However, state-of-the-art multicast protocols are designed to perform in single-hop mode with a single session, leading to under-utilization of the scarce spectrum resource. In this paper, we propose YMMV, a novel multicast protocol that jointly considers MIMO and cooperative communications in OFDMA networks. The base station transmits data in multiple sessions using multiple antennas on the same channel to exploit spatial multiplexing in MIMO. Further, cooperative transmission on different channels among users is also utilized. We tackle the resulted session scheduling problem in YMMV, where the multi- channel characteristic of OFDMA further aggravates the difficulty of efficient algorithm design. With rigorous analysis and extensive simulations, we show that our multi-session multicast protocol is able to improve throughput performance significantly.

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... The authors in [19] studied the lower-bound for the outage probability of cooperative multi-antenna multicasting schemes based on the amplify-and-forward (AF) strategy where the users are equipped with a single antenna. In [20], multicast scheduling with multiple sessions and multiple channels was investigated where the base station may multicast data in two sessions using MIMO simultaneously through the same channel and the users are allowed to cooperatively help each other on orthogonal channels. Thus, the scheme in [20] leads to a higher multicasting rate than single-session transmissions. ...
... In [20], multicast scheduling with multiple sessions and multiple channels was investigated where the base station may multicast data in two sessions using MIMO simultaneously through the same channel and the users are allowed to cooperatively help each other on orthogonal channels. Thus, the scheme in [20] leads to a higher multicasting rate than single-session transmissions. Joint transmit and relay precoding design problems were investigated in [21], [22] for a two-hop multicasting MIMO relay system where all nodes are equipped with multiple antennas. ...
... Numerical simulations demonstrate the effectiveness of the proposed algorithms. Note that the proposed algorithms support multicasting multiple data streams in contrast to the existing single data stream multicasting schemes [3]- [20]. In this paper, for notational convenience, we consider a narrow-band single-carrier system. ...
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... However, in the case of long source-destination distance, relay node(s) is necessary to efficiently combat the pathloss of wireless channel. In [11], the authors investigated multicast scheduling with multiple sessions and multiple channels where the base station may multicast data in two sessions using MIMO simultaneously through the same channel and the users are allowed to cooperatively help each other on orthogonal channels. The authors in [12] studied the lower bound for the outage probability of cooperative multiple antenna multicasting schemes based on amplify-and-forward (AF) strategy where the users are equipped with a single antenna. ...
... Numerical simulations are performed to demonstrate the effectiveness of the proposed algorithm. Note that in contrast to our system, the second-hop receivers are equipped with a single antenna in [11]- [12]. ...
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... Numerical simulations demonstrate the effectiveness of the proposed algorithms. Note that both algorithms support multicasting multiple data streams in contrast to the existing single data stream multicasting schemes [2][16]. Interestingly, we show that for the special case of single data stream multicasting, the relay precoding matrix optimization problem can be equivalently converted to the transmit beamforming problem for single-hop multicasting systems. ...
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IEEE Standard for Local and metropolitan area networks, Part 16: Air Interface for Fixed and Mobile Broadband Wireless Access Systems
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