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Petar Popovski - One of the best experts on this subject based on the ideXlab platform.

  • zero outage Cellular downlink with fixed rate d2d underlay
    2015
    Co-Authors: Nuno K Pratas, Petar Popovski
    Abstract:

    Two of the emerging trends in wireless Cellular systems are Device-to-Device (D2D) and machine-to-machine (M2M) communications. D2D enables efficient reuse of the licensed spectrum to support localized transmissions, while M2M connections are often characterized by fixed and low transmission rates. D2D connections can be instrumental in localized aggregation of uplink M2M traffic to a more capable Cellular Device, before being finally delivered to the base station (BS). In this paper we show that a fixed M2M rate is an enabler of efficient machine-type D2D underlay operation taking place simultaneously with another downlink Cellular transmission. In the considered scenario, a BS $B$ transmits to a user $U$ , while there are $N_{M}$ machine-type Devices (MTDs) attached to $U$ , all sending simultaneously to $U$ and each using the same rate $R_{M}$ . While assuming that $B$ knows the channel $B-U$ , but not the interfering channels from the MTDs to $U$ , we prove that there is a positive downlink rate that can always be decoded by $U$ , leading to zero-outage of the downlink signal. This is a rather surprising consequence of the features of the multiple access channel and the fixed rate $R_{M} $ . We also consider the case of a simpler, single-user decoder at $U$ with successive interference cancellation. However, with single-user decoder, a positive zero-outage rate exists only when $N_{M}=1$ and is zero when $N_{M} >1$ . This implies that joint decoding is instrumental in enabling fixed-rate underlay operation.

  • zero outage Cellular downlink with fixed rate d2d underlay
    2014
    Co-Authors: Nuno K Pratas, Petar Popovski
    Abstract:

    Two of the emerging trends in wireless Cellular systems are Device-to-Device (D2D) and Machine-to-Machine (M2M) communications. D2D enables efficient reuse of the licensed spectrum to support localized transmissions, while M2M connections are often characterized by fixed and low transmission rates. D2D connections can be instrumental in localized aggregation of uplink M2M traffic to a more capable Cellular Device, before being finally delivered to the Base Station (BS). In this paper we show that a fixed M2M rate is an enabler of efficient Machine-Type D2D underlay operation taking place simultaneously with another \emph{downlink} Cellular transmission. In the considered scenario, a BS $B$ transmits to a user $U$, while there are $N_M$ Machine-Type Devices (MTDs) attached to $U$, all sending simultaneously to $U$ and each using the same rate $R_M$. While assuming that $B$ knows the channel $B-U$, but not the interfering channels from the MTDs to $U$, we prove that there is a positive downlink rate that can always be decoded by $U$, leading to zero-outage of the downlink signal. This is a rather surprising consequence of the features of the multiple access channel and the fixed rate $R_M$. We also consider the case of a simpler, single-user decoder at $U$ with successive interference cancellation. However, with single-user decoder, a positive zero-outage rate exists only when $N_M=1$ and is zero when $N_M>1$. This implies that joint decoding is instrumental in enabling fixed-rate underlay operation.

Nuno K Pratas - One of the best experts on this subject based on the ideXlab platform.

  • zero outage Cellular downlink with fixed rate d2d underlay
    2015
    Co-Authors: Nuno K Pratas, Petar Popovski
    Abstract:

    Two of the emerging trends in wireless Cellular systems are Device-to-Device (D2D) and machine-to-machine (M2M) communications. D2D enables efficient reuse of the licensed spectrum to support localized transmissions, while M2M connections are often characterized by fixed and low transmission rates. D2D connections can be instrumental in localized aggregation of uplink M2M traffic to a more capable Cellular Device, before being finally delivered to the base station (BS). In this paper we show that a fixed M2M rate is an enabler of efficient machine-type D2D underlay operation taking place simultaneously with another downlink Cellular transmission. In the considered scenario, a BS $B$ transmits to a user $U$ , while there are $N_{M}$ machine-type Devices (MTDs) attached to $U$ , all sending simultaneously to $U$ and each using the same rate $R_{M}$ . While assuming that $B$ knows the channel $B-U$ , but not the interfering channels from the MTDs to $U$ , we prove that there is a positive downlink rate that can always be decoded by $U$ , leading to zero-outage of the downlink signal. This is a rather surprising consequence of the features of the multiple access channel and the fixed rate $R_{M} $ . We also consider the case of a simpler, single-user decoder at $U$ with successive interference cancellation. However, with single-user decoder, a positive zero-outage rate exists only when $N_{M}=1$ and is zero when $N_{M} >1$ . This implies that joint decoding is instrumental in enabling fixed-rate underlay operation.

  • zero outage Cellular downlink with fixed rate d2d underlay
    2014
    Co-Authors: Nuno K Pratas, Petar Popovski
    Abstract:

    Two of the emerging trends in wireless Cellular systems are Device-to-Device (D2D) and Machine-to-Machine (M2M) communications. D2D enables efficient reuse of the licensed spectrum to support localized transmissions, while M2M connections are often characterized by fixed and low transmission rates. D2D connections can be instrumental in localized aggregation of uplink M2M traffic to a more capable Cellular Device, before being finally delivered to the Base Station (BS). In this paper we show that a fixed M2M rate is an enabler of efficient Machine-Type D2D underlay operation taking place simultaneously with another \emph{downlink} Cellular transmission. In the considered scenario, a BS $B$ transmits to a user $U$, while there are $N_M$ Machine-Type Devices (MTDs) attached to $U$, all sending simultaneously to $U$ and each using the same rate $R_M$. While assuming that $B$ knows the channel $B-U$, but not the interfering channels from the MTDs to $U$, we prove that there is a positive downlink rate that can always be decoded by $U$, leading to zero-outage of the downlink signal. This is a rather surprising consequence of the features of the multiple access channel and the fixed rate $R_M$. We also consider the case of a simpler, single-user decoder at $U$ with successive interference cancellation. However, with single-user decoder, a positive zero-outage rate exists only when $N_M=1$ and is zero when $N_M>1$. This implies that joint decoding is instrumental in enabling fixed-rate underlay operation.

Vincent H Poor - One of the best experts on this subject based on the ideXlab platform.

  • hypergraph based wireless distributed storage optimization for Cellular d2d underlays
    2016
    Co-Authors: Li Wang, Wei Chen, Huaqing Wu, Yinan Ding, Vincent H Poor
    Abstract:

    Distributed storage that leverages Cellular Device-to-Device (D2D) underlay has attracted rising research interest due to its potential to offload Cellular traffic, improve spectral efficiency and energy efficiency, and reduce transmission delay. This paper investigates the overall transmission cost minimization problem based on a content encoding strategy to download a new content item or repair a lost content item in D2D-based distributed storage systems while guaranteeing users’ quality of service. In addition to the optimization of the coding parameters, the cost minimization problem also considers the distribution of content items, the selection of content helpers for each content requester, and the spectrum reuse for establishing D2D links in between. Formulating a hypergraph-based three-dimensional matching problem among content helpers, requesters, and Cellular user resources, we present a local search based algorithm with low complexity for optimization. Numerical results demonstrate the performance and the effectiveness of our proposed approach.

Ekram Hossain - One of the best experts on this subject based on the ideXlab platform.

  • discovering mobile applications in Cellular Device to Device communications hash function and bloom filter based approach
    2016
    Co-Authors: Kae Won Choi, Dimas Tribudi Wiriaatmadja, Ekram Hossain
    Abstract:

    We propose a code-based discovery protocol for Cellular Device-to-Device (D2D) communications. To realize proximity-based services such as mobile social networks and mobile marketing using D2D communications, each Device should first discover nearby Devices, which have mobile applications of interest, by using a discovery protocol. The proposed discovery protocol makes use of a short discovery code that contains compressed information of mobile applications in a Device. A discovery code is generated by using either a hash function or a Bloom filter. When a Device receives a discovery code broadcast by another Device, the Device can approximately find out the mobile applications in the other Device. The proposed protocol is capable of quickly discovering massive number of Devices while consuming a relatively small amount of radio resources. We analyze the performance of the proposed protocol under the random direction mobility model and a real mobility trace. By simulations, we show that the analytical results well match the simulation results and that the proposed protocol greatly outperforms a simple non-filtering protocol.

Li Wang - One of the best experts on this subject based on the ideXlab platform.

  • hypergraph based wireless distributed storage optimization for Cellular d2d underlays
    2016
    Co-Authors: Li Wang, Wei Chen, Huaqing Wu, Yinan Ding, Vincent H Poor
    Abstract:

    Distributed storage that leverages Cellular Device-to-Device (D2D) underlay has attracted rising research interest due to its potential to offload Cellular traffic, improve spectral efficiency and energy efficiency, and reduce transmission delay. This paper investigates the overall transmission cost minimization problem based on a content encoding strategy to download a new content item or repair a lost content item in D2D-based distributed storage systems while guaranteeing users’ quality of service. In addition to the optimization of the coding parameters, the cost minimization problem also considers the distribution of content items, the selection of content helpers for each content requester, and the spectrum reuse for establishing D2D links in between. Formulating a hypergraph-based three-dimensional matching problem among content helpers, requesters, and Cellular user resources, we present a local search based algorithm with low complexity for optimization. Numerical results demonstrate the performance and the effectiveness of our proposed approach.