Implementation Aspects in DFT Modulated Filter Bank Transceivers for Cognitive Radio
Nour Mansour,
Dirk Dahlhaus
Issue:
Volume 2, Issue 4-1, December 2014
Pages:
1-10
Received:
12 September 2014
Accepted:
4 November 2014
Published:
18 November 2014
Abstract: Discrete Fourier transform (DFT) modulated filter banks (FBs) are considered as strong tools used to implement both dynamic spectrum access and spectrum sensing in cognitive radio (CR) systems. High time-frequency (TF) resolution for spectral estimation and effective spectrum access with low complexity transceivers are the basic objectives in CR systems. However, the limitations of self-interference in DFT FBs as well as a primary user interference increase the overall transceiver complexity. In this paper, we design DFT modulated FBs which take into account the aforementioned contradicting requirements of high resolution capabilities, efficient spectrum access and affordable implementation effort for an additive white Gaussian channel. Four simple designs are presented and their performance are investigated and compared for a CR system with basic transmission parameters resembling those of IEEE 802.11g.
Abstract: Discrete Fourier transform (DFT) modulated filter banks (FBs) are considered as strong tools used to implement both dynamic spectrum access and spectrum sensing in cognitive radio (CR) systems. High time-frequency (TF) resolution for spectral estimation and effective spectrum access with low complexity transceivers are the basic objectives in CR sy...
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A Novel High Spectral Efficiency Waveform Coding-OVTDM
Issue:
Volume 2, Issue 4-1, December 2014
Pages:
11-26
Received:
7 October 2014
Accepted:
29 November 2014
Published:
27 December 2014
Abstract: Different from other Coding, based on the Overlapped Multiplexing Principle discovered by author， a novel OVTDM (Overlapped Time Division Multiplexing) Waveform Coding is proposed. Instead of the encoding matrix and mapped signal constellation, any engineering sense band-limited Multiplexing Waveform can be employed. By its data weighted shift overlapped versions, the coding gain and spectral efficiency are both achieved. The heavier the overlap of the data weighted Multiplexing Waveform, the higher the coding gain and spectral efficiency as well as the closer the output to the optimum complex Gaussian distribution. The encoder structures, parameters, optimum and fast decoding algorithms, pre-coding, some implementation problems as well as the bit error performance are estimated and discussed. Simulations show that OVTDM is suitable for high spectral efficiency applications and its spectral efficiency is roughly proportional to SNR.
Abstract: Different from other Coding, based on the Overlapped Multiplexing Principle discovered by author， a novel OVTDM (Overlapped Time Division Multiplexing) Waveform Coding is proposed. Instead of the encoding matrix and mapped signal constellation, any engineering sense band-limited Multiplexing Waveform can be employed. By its data weighted shift over...
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