通信類外文文獻翻譯--蜂窩網絡中的全雙工通信設備(英文)_第1頁
已閱讀1頁,還剩4頁未讀, 繼續(xù)免費閱讀

下載本文檔

版權說明:本文檔由用戶提供并上傳,收益歸屬內容提供方,若內容存在侵權,請進行舉報或認領

文檔簡介

1、Full Duplex Device to Device Communication in Cellular NetworksSanghoon Kim and Wayne Stark University of Michigan, Ann Arbor, MI 48109 kimsangh@umich.edu / stark@umich.eduAbstract—In this paper, we investigate the perfo

2、rmance im- provements of single band full duplex device to device commu- nication that can transmit and received on the same frequency band in cellular networks. In cellular networks, two separate frequencies are used to

3、 enable simultaneous transmission and reception for half duplex radios. Recently, full duplex radios that allows a wireless node to simultaneously transmit and receive in one frequency band were proposed. It was shown th

4、at it was effective for short-range communications. As such, full duplex communication is adequate for device to device (D2D) communi- cation, which is usually a short range communication. Device to device communication

5、is an underlay scheme for cellular networks that enables peer-to-peer local services with limited impact on the primary cellular network. When user devices are closer to each other than the base station, D2D communicatio

6、n can improve the bandwidth efficiency of the communication between the users. When full duplex communication is adopted for D2D communication, it requires only one frequency band for two way communication between the lo

7、cal users. It improves the bandwidth efficiency for D2D communication. We propose a simple full duplex D2D communication protocol and analyze the bandwidth performance gain of the protocol compared to the legacy cellular

8、 communication scheme.I. INTRODUCTIONWireless networks are often limited in either the bandwidth efficiency or energy efficiency. Cellular networks which use a significant amount of infrastructure generally require com-

9、munication between two users to go through a base station. If the two users are in close proximity this is an inefficient use of the frequency spectrum and energy, especially if the communications involves a substantial

10、amount of data. Device- to-device communications where communications takes place directly between two devices rather than through some infras- tructure has the challenge of deciding when device-to-device communication i

11、s appropriate and then the design of the ap- propriate protocol. Device-to-device communication has been included in standards such as IEEE 802.11 in a distributed fashion. In an IEEE 802.11 network, a wireless node sens

12、es the channel and decides whether it can send a packet or not. In distributed wireless networks nodes employ a collision avoid- ance mechanism such as CSMA/CA or RTS/CTS protocol. While an access point (AP) is typically

13、 used in an IEEE 802.11 networks, the AP does not directly control either the channel access or the resource allocation. However, device-to-device communication has not been used in cellular networks. In cellular network

14、s information is delivered to the destination user equipment (UE) through base stations. The base stationgenerally controls channel access and allocates resources even when the communication is between UEs in the same ce

15、ll. Incorporating D2D communication as a possibility in cel- lular communication can improve the efficiency of cellular networks. When the UEs are close to each other compared to the distance to the base station, D2D com

16、munication is more energy and bandwidth efficient than communications through a base station. Figure 2 illustrates a case which the D2D communication is more efficient.Because the channel access and resources are control

17、led by the base station, the D2D communication in cellular networks should also be controlled by the base station. Thus, the base station grants approval for D2D communication between local UEs in the same cell only if i

18、t is more efficient than the legacy communication through the base station. Communication using D2D is appropriate for UE nodes in close proximity. When the distance between UE nodes increases, D2D communication throughp

19、ut degrades drastically [1]. Because of the proximity, D2D communication requires less resources than the normal cellular communica- tion, which leads to the improved total cell capacity [2]. A coordinated resource alloc

20、ation for D2D communication to manage the interference has been proposed [3]. We model D2D communication as a form of wireless communications that supports proximity based application services. One example appropriate fo

21、r full duplex D2D com- munications is when mobile users want to play a popular game with another mobile user in the area. File, image, or video sharing between users in proximity is another example appropriate for D2D co

22、mmunication. As more social service or proximity based service become available through mobile devices, there will be more need for D2D communications. Full duplex communication is typically implemented using either freq

23、uency division multiplexing or time division mul- tiplexing. In order for D2D communications to take place it is necessary that radios are capable transmitting and receiving on a single frequency. However, strong self in

24、terference at the receive antenna from the simultaneous transmission at the transmit antenna presents a challenge in implementation. A combination of analog and digital interference cancellation can suppress the self int

25、erference [4] and [5]. A full duplex radio with two antennas has been implemented and shown to achieve better performance than the half duplex 2x2 MIMO communication at low transmit power levels [5]. In [6] and [7], MAC

26、protocols using full duplex communication were proposed in the context of an ad-hoc network. The adoption2014 International Conference on Computing, Networking and Communications, Wireless Networks Symposium978-1-4799-23

27、58-8/14/$31.00 ©2014 IEEE 721this paper we assume the first step is successful and only consider the second step and actual D2D communication. We assume that the channel state such as path loss and fading between th

28、e UEs for D2D communication is known to the users through the discovery procedure. In protocols such as Flashlinq [9], a special type of beacon is used to broadcast or discover service and UEs estimate the channel to oth

29、er user devices by hearing the beacon. Because full duplex communication can transmit and re- ceive on the same frequency band, it can improve the band- width efficiency of a cell. When D2D communication is used for comm

30、unication between two UEs in the same cell, it uses half bandwidth compared to infrastructure based com- munication (FDD). Figure 2 illustrates the difference between the full duplex D2D communication and infrastructure

31、based communication. When a user device communicates with the base station, it uses both antennas in half duplex mode.When a user device adopt D2D communication, it utilizes full duplex communication which uses 1 antenna

32、 for each direction.D. Infrastructure based communication modelWe assume that the frequency division duplexing based cellular communication is used in cellular networks. There can be two cases for the infrastructure base

33、d communication. The first case is the communication between the UEs in the same cell. In our protocol, UE requests D2D communication when it needs to communicate with another UE in the same cell. When the base station d

34、etermines that the legacy cellular communication is more efficient than D2D communication, two UEs communicate through the base station. In this case, double frequency bands are needed for communication. Each frequency b

35、and is allocated to each UE for communications with the base station. For the communication between a UE and the base station, FDD is used. We assume half of the allocated bandwidth is used for uplink and the other half

36、is used for downlink. The bandwidth allocation for D2D communication is described in the next chapter. The second case is an UE connects to an entity outside the cell. The entity can be either a server on the internet or

37、 another UE in another cell. For both cases, we only consider the overhead between a UE and the base station. The communication of the second case cannot be replaced by D2D communication and is the same with legacy cellu

38、lar communication. For the comparison with D2D communication, we consider the bandwidth efficiency of infrastructure based communica- tion. We assume that 2x2 MIMO communication is used and the communication achieves the

39、 2x2 MIMO channel capacity with the channel state information at the receiver. Then the capacity is [11]C = EH?log det?I2×2 + 1NHH?2??(3)where N is the noise variance and H is the channel matrix for 2×2 MIMO co

40、mmunication. In practical cellular communica- tions systems, there is overhead transmissions such as control or signaling information that needs to be exchanged betweenBase StationD2D CommunicationD2D CommunicationFig. 3

41、. Full duplex communication systemthe user and the base station. However, in this paper we only consider the actual packet transmission because the amount of overhead needed for both D2D communication and cellular commun

42、ication are comparable.III. FULL DUPLEX D2D COMMUNICATION PROTOCOLA. D2D communication setupIn this section, we describe the D2D communication setup protocol. A UE requests D2D communication with another UE via the base

43、station and include the D2D channel state information in the request. When D2D communication is more efficient than cellular communication, the base station assigns a frequency band for D2D communication. Figure 3 illust

44、rates a cell with D2D communication functionality. We assume the channel state between UEs and the base station is known to the base station by the reference signals in cellular communication [12]. When the base station

45、finds that the infrastructure communication is more efficient than the proposed D2D communication, it allocates resources for the communication through the base station. When D2D commu- nication is completed, the devices

46、 inform the base station of such in order to reallocate the resource.B. Criteria for D2D communicationWith the given channel state information, the base station determines whether the D2D communication is more efficient

47、than the communication through the base station. Let hD2D, be the 1x1 channel state for D2D communication. Let Hb,i is the 2x2 channel state between user i and the base station. When two UEs have packets to transmit to e

48、ach other consisting of M bits. We assume the channel reciprocity for D2D com- munication. Then the time consumption for two way packet transmission using full duplex D2D communication isTD2D = MWE[log2 (1 + |hD2D|2SINR)

49、] (4)where SINR is given in (2). The time consumption for the two way packet transmission in a cell using infrastructure2014 International Conference on Computing, Networking and Communications, Wireless Networks Symposi

溫馨提示

  • 1. 本站所有資源如無特殊說明,都需要本地電腦安裝OFFICE2007和PDF閱讀器。圖紙軟件為CAD,CAXA,PROE,UG,SolidWorks等.壓縮文件請下載最新的WinRAR軟件解壓。
  • 2. 本站的文檔不包含任何第三方提供的附件圖紙等,如果需要附件,請聯系上傳者。文件的所有權益歸上傳用戶所有。
  • 3. 本站RAR壓縮包中若帶圖紙,網頁內容里面會有圖紙預覽,若沒有圖紙預覽就沒有圖紙。
  • 4. 未經權益所有人同意不得將文件中的內容挪作商業(yè)或盈利用途。
  • 5. 眾賞文庫僅提供信息存儲空間,僅對用戶上傳內容的表現方式做保護處理,對用戶上傳分享的文檔內容本身不做任何修改或編輯,并不能對任何下載內容負責。
  • 6. 下載文件中如有侵權或不適當內容,請與我們聯系,我們立即糾正。
  • 7. 本站不保證下載資源的準確性、安全性和完整性, 同時也不承擔用戶因使用這些下載資源對自己和他人造成任何形式的傷害或損失。

評論

0/150

提交評論