Subband Filtered Multi-carrier Systems for Multi-service Wireless Communications

Subband Filtered Multi-carrier Systems forMulti-service Wireless Communications

 

ABSTRACT:

Flexibly supporting multiple services, each with different communication requirements and frame structure, hasbeen identified as one of the most significant and promisingcharacteristics of next generation and beyond wireless communicationsystems. However, integrating multiple frame structureswith different subcarrier spacing in one radio carrier mayresult in significant inter-service-band-interference (ISBI). In thispaper, a framework for multi-service (MS) systems is establishedbased on subband filtered multi-carrier system. The subbandfiltering implementations and both asynchronous and generalizedsynchronous (GS) MS subband filtered multi-carrier (SFMC)systems have been proposed. Based on the GS-MS-SFMC system,the system model with ISBI is derived and a number of propertieson ISBI are given. In addition, low-complexity ISBI cancelationalgorithms are proposed by precoding the information symbolsat the transmitter. For asynchronous MS-SFMC system in thepresence of transceiver imperfections including carrier frequencyoffset, timing offset and phase noise, a complete analyticalsystem model is established in terms of desired signal, intersymbol-interference, inter-carrier-interference, ISBI and noise.Thereafter, new channel equalization algorithms are proposedby considering the errors and imperfections. Numerical analysisshows that the analytical results match the simulation results,and the proposed ISBI cancelation and equalization algorithmscan significantly improve the system performance in comparisonwith the existing algorithms.

 OBJECTIVE:

  • To reduce OoB emission level for next generation communications.
  • Low-complexity baseband signal processing algorithms to precancel the ISBI by pre-coding the information symbols beforetransmission.
  • To investigate the impacts of transceiver imperfectionsincluding carrier frequency offset (CFO), timing offset (TO)and phase noise (PN) on the performance.

 INTRODUCTION:

The next generation wireless communication (5G and beyond) is required to support a greater density of users, higherdata throughput, ultra-high reliability and ultra-low latencycommunications to meet the vision of “everything everywhereand always connected” with “provision of perception of infinite capacity”. However, these multi-fold requirementsare generally driven by different type of services and use cases,resulting in different optimal radio frame structure design criteria. For example, the service for machine type communications(MTC) might require smaller subcarrier spacing (thus largersymbol duration) to support massive delay-tolerant devices. Vehicle to vehicle (V2V) communications, on theother hand, have more stringent latency requirements, thus,symbol duration might be significantly reduced.

 EXISTING SYSTEM:

  1. Zhang, M. Jia, L. Chen, J. Ma, and J. Qiu, “Filtered-OFDM – enablerfor flexible waveform in the 5th generation cellular networks,” in IEEEGlobecom, 2015, pp. 1–6.

One viable solution is to divide the system bandwidth into severalservice bands with each used for a different type of service.

5GNOW, “D3.2: 5G waveform candidate selection,” Tech. Rep., 2014

Subband filtered multi-carrier (SFMC) based systems including universal filtered multi-carrier (UFMC).

 DRAWBACKS:

  • Different optimal radio frame structure design criteria.
  • Reduction in spectrum efficiency.
  • It comes at the expense.
  • Compromised accuracy and increased system complexity.

 PROPOSED SYSTEM:

In thispaper, a framework for multi-service (MS) systems is establishedbased on subband filtered multi-carrier system. The subbandfiltering implementations and both asynchronous and generalizedsynchronous (GS) MS subband filtered multi-carrier (SFMC)systems have been proposed. Based on the GS-MS-SFMC system,the system model with ISBI is derived and a number of propertieson ISBI are given. In addition, low-complexity ISBI cancelationalgorithms are proposed by precoding the information symbolsat the transmitter. For asynchronous MS-SFMC system in thepresence of transceiver imperfections including carrier frequencyoffset, timing offset and phase noise, a complete analytical system model is established in terms of desired signal, intersymbol-interference, inter-carrier interference, ISBI and noise.

 BLOCK DIAGRAM:

Subband Filtered Multi-carrier Systems forMulti

DESCRIPTION:

  • We first build a framework for MS-SFMC system and categorize the possible subband filtering implementations and synchronized systems in frequency and time domains, respectively.
  • Based on the GS system and one of the SFMC implementations, i.e, UFMC, and in the absence of transceiver imperfections and sufficient guard interval between symbols, we first establish a system model for MS-UFMC systems with arbitrary values of subcarrier spacing and GB.
  • In the presence of transceiver imperfections for asynchronous MS system, we derive an analytical expression for MS-UFMC system in terms of desired signal,
    inter-carrier interference (ICI), inter-symbol interference (ISI), ISBI and noise by considering CFO, TO, PN and insufficient ZP length between symbols. Based on the analytical framework, we propose channel equalization algorithms that can provide significant gain in terms of BER performance in comparison to OFDM and the stateof-the-art (SoTA) UFMC systems.

ADVANTAGES:

  • All of thederivations and propositions are also applicable to OFDM
    systems as a special case.
  • An analyticalsystem model was established to analyze the desired signal,
    ISI, ICI, ISBI and noise.
  • Channel equalizationalgorithms were proposed by considering the errors and imperfections based on the derived signal models.

SYSTEM REQUIREMENTS:

HARDWARE REQUIREMENTS:

  • System : Pentium Dual Core.
  • Hard Disk : 120 GB.
  • Monitor : 15’’ LED
  • Input Devices : Keyboard, Mouse
  • Ram :

SOFTWARE REQUIREMENTS:

  • Operating system : Windows 7.
  • Coding Language : MATLAB
  • Tool : MATLAB R2013A

REFERENCE:

Lei Zhang, Ayesha Ijaz, Pei Xiao, Atta Quddus and Rahim Tafazolli, “Subband Filtered Multi-carrier Systems forMulti-service Wireless Communications”, IEEE Transactions on Wireless Communications, 2017.

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