The Experts below are selected from a list of 669 Experts worldwide ranked by ideXlab platform

D.l. Noneaker - One of the best experts on this subject based on the ideXlab platform.

  • Performance of Serial, Matched-Filter Packet Acquisition using a Preamble-Sequence Acceptance Criterion
    MILCOM 2006, 2006
    Co-Authors: J. Schloemann, D.l. Noneaker
    Abstract:

    In this paper, we introduce a simple method to improve the performance of threshold-based serial, matched-filter acquisition in packet radio communications. Each packet transmission includes a fixed-length acquisition Preamble, and the Preamble Sequence used in packet transmissions is changed at predetermined times based on a Sequence-generation algorithm. Two classes of Sequence-generation algorithms are considered: random Sequence generation, and Preamble Sequence generation based on m-Sequences. Both are used in conjunction with a Sequence-acceptance criterion based on the sidelobe energy of the Preamble Sequence. The tradeoff between the acquisition performance and the stringency of the acceptance criterion is examined for each Sequence-generation algorithm. The computational burden of the search for an acceptable Preamble Sequence is also considered. It is shown that the use of the m-Sequence generation algorithm results in much poorer acquisition performance for a given percentage of accepted candidate Preamble Sequences than is predicted using the model of a random Sequence generator. Moreover, it is shown that that the tradeoff between acquisition performance and the computation required to find an acceptable Preamble Sequence is comparable for all of the m-Sequence generators considered. Thus within the class of m-Sequence generation algorithms, the use of a longer-period m-Sequence generator results in a larger number of acceptable Preamble Sequences for a given level of acquisition performance and Sequence-search computation.

  • A technique to improve the performance of serial, matched-filter acquisition in direct-Sequence spread-spectrum packet radio communications
    IEEE Journal on Selected Areas in Communications, 2005
    Co-Authors: Arvind Swaminathan, D.l. Noneaker
    Abstract:

    In this paper, we examine a simple method to improve the performance of serial, matched-filter acquisition in direct-Sequence spread-spectrum packet radio communications. Each packet transmission includes an acquisition Preamble, and the Preamble Sequence is changed at the boundaries of predefined time epochs based on a pseudorandom Sequence generator. It is shown in previous work that the presence of an intermediate-frequency filter and the characteristics of the automatic gain-control subsystem lead to a probability of not acquiring that is a nonmonotonic function of the signal-to-noise ratio if the acquisition algorithm uses a threshold-crossing detector with a fixed threshold. The acquisition algorithm presented in this paper employs an estimator to adaptively select the acquisition threshold for each test statistic. It is shown that this technique reduces the severity of the nonmonotonicity and substantially improves the acquisition performance.

  • Performance of serial, matched-filter acquisition with adaptive thresholds in direct-Sequence packet communications
    MILCOM 2002. Proceedings, 1
    Co-Authors: Arvind Swaminathan, D.l. Noneaker
    Abstract:

    In this paper we examine a technique to improve the performance of serial, matched-filter acquisition in direct-Sequence spread-spectrum packet radio communications. Each packet transmission includes an acquisition Preamble, and the Preamble Sequence is changed at the boundaries of predefined time epochs based on a pseudorandom Sequence generator. The acquisition algorithm considered in this paper exploits knowledge of the Preamble Sequence employed during each time epoch to adaptively choose the acquisition threshold. The performance of the adaptive-threshold acquisition algorithm is evaluated and compared with one previously considered in Noneaker et al. (2001) in which the threshold is fixed. It is shown that the adaptive-threshold algorithm results in good average performance, even with a large a priori uncertainty in the signal-to-noise ratio. It is also shown that the average performance with the adaptive threshold is superior to that obtained with the fixed-threshold algorithm of Noneaker.

  • ICC - A technique to improve the performance of serial, matched-filter acquisition in direct-Sequence spread-spectrum packet radio communications
    IEEE International Conference on Communications 2003. ICC '03., 1
    Co-Authors: Arvind Swaminathan, D.l. Noneaker
    Abstract:

    In this paper we examine a simple method to improve the performance of serial, matched-filter acquisition indirect-Sequence spread-spectrum packet radio communications. Each packet transmission includes an acquisition Preamble, and the Preamble Sequence is changed at the boundaries of predefined time epochs based on a pseudorandom Sequence generator. It is shown in previous work that the presence of an IF filter and the characteristics of the AGC subsystem, lead to a probability of not acquiring that is a non-monotonic function of the signal-to-noise ratio if the acquisition algorithm uses a threshold-crossing detector with a fixed threshold. The acquisition algorithm presented in this paper employs an estimator to adaptively select the acquisition threshold. It is shown that this technique reduces the severity of the non-monotonicity and substantially improves the acquisition performance.

Yong-soo Cho - One of the best experts on this subject based on the ideXlab platform.

  • A Preamble Sequence Design Techniqe for Efficient Beam ID Detection in Millimeter-Wave Cellular Systems
    IEEE Transactions on Vehicular Technology, 2016
    Co-Authors: Yeong Jun Kim, Dae Gen Han, Yong-soo Cho
    Abstract:

    The beam training protocol in millimeter-wave cellular systems requires a long processing time that is proportional to the product of the number of Tx beams, number of Rx beams, and number of neighbor base stations. In this paper, a Preamble design technique that can significantly reduce the processing time for beam training in an orthogonal-frequency-division-multiplexing-based cellular system is proposed by transmitting multiple beams with their corresponding Tx beam IDs (BIDs) and cell ID (CID). The Zadoff-Chu (ZC) Sequence, with its length given by a multiplication of two prime numbers, is proposed for an efficient CID and BID (CBID) search in a Preamble design. It is shown by computer simulation that the proposed Preamble design technique can obtain a 10- to 20-fold computational complexity gain in CBID detection and achieve a performance (0.1-dB signal-to-noise ratio shift) that is close to that of a ZC Sequence with a prime length.

  • Efficient Preamble Design Technique for Millimeter-Wave Cellular Systems with Beamforming.
    Sensors, 2016
    Co-Authors: Dae Geun Han, Yeong Jun Kim, Yong-soo Cho
    Abstract:

    The processing time for beam training in millimeter-wave (mmWave) cellular systems can be significantly reduced by a code division multiplexing (CDM)-based technique, where multiple beams are transmitted simultaneously with their corresponding Tx beam IDs (BIDs) in the Preamble. However, mmWave cellular systems with CDM-based Preambles require a large number of cell IDs (CIDs) and BIDs, and a high computational complexity for CID and BID (CBID) searches. In this paper, a new Preamble design technique that can increase the number of CBIDs significantly is proposed, using a Preamble Sequence constructed by a combination of two Zadoff-Chu (ZC) Sequences. An efficient technique for the CBID detection is also described for the proposed Preamble. It is shown by simulations using a simple model of an mmWave cellular system that the proposed technique can obtain a significant reduction in the complexity of the CBID detection without a noticeable performance degradation, compared to the previous technique.

  • ICUFN - Preamble design technique for millimeter-wave cellular systems using Zadoff-Chu Sequences
    2016 Eighth International Conference on Ubiquitous and Future Networks (ICUFN), 2016
    Co-Authors: Dae Gen Han, Yeong Jun Kim, Yong-soo Cho
    Abstract:

    In this paper, a new Preamble design technique that can increase the number of cell IDs (CIDs) and beam IDs (BIDs) significantly is proposed, using a Preamble Sequence constructed by a combination of two Zadoff-Chu (ZC) Sequences. An efficient technique for the CID and BID (CBID) detection is also described for the proposed Preamble. It is shown by simulations using a simple model of an mmWave cellular system that the proposed technique can obtain a significant reduction in the complexity of the CBID detection without a noticeable performance degradation, compared to the previous technique.

Arvind Swaminathan - One of the best experts on this subject based on the ideXlab platform.

  • A technique to improve the performance of serial, matched-filter acquisition in direct-Sequence spread-spectrum packet radio communications
    IEEE Journal on Selected Areas in Communications, 2005
    Co-Authors: Arvind Swaminathan, D.l. Noneaker
    Abstract:

    In this paper, we examine a simple method to improve the performance of serial, matched-filter acquisition in direct-Sequence spread-spectrum packet radio communications. Each packet transmission includes an acquisition Preamble, and the Preamble Sequence is changed at the boundaries of predefined time epochs based on a pseudorandom Sequence generator. It is shown in previous work that the presence of an intermediate-frequency filter and the characteristics of the automatic gain-control subsystem lead to a probability of not acquiring that is a nonmonotonic function of the signal-to-noise ratio if the acquisition algorithm uses a threshold-crossing detector with a fixed threshold. The acquisition algorithm presented in this paper employs an estimator to adaptively select the acquisition threshold for each test statistic. It is shown that this technique reduces the severity of the nonmonotonicity and substantially improves the acquisition performance.

  • Performance of serial, matched-filter acquisition with adaptive thresholds in direct-Sequence packet communications
    MILCOM 2002. Proceedings, 1
    Co-Authors: Arvind Swaminathan, D.l. Noneaker
    Abstract:

    In this paper we examine a technique to improve the performance of serial, matched-filter acquisition in direct-Sequence spread-spectrum packet radio communications. Each packet transmission includes an acquisition Preamble, and the Preamble Sequence is changed at the boundaries of predefined time epochs based on a pseudorandom Sequence generator. The acquisition algorithm considered in this paper exploits knowledge of the Preamble Sequence employed during each time epoch to adaptively choose the acquisition threshold. The performance of the adaptive-threshold acquisition algorithm is evaluated and compared with one previously considered in Noneaker et al. (2001) in which the threshold is fixed. It is shown that the adaptive-threshold algorithm results in good average performance, even with a large a priori uncertainty in the signal-to-noise ratio. It is also shown that the average performance with the adaptive threshold is superior to that obtained with the fixed-threshold algorithm of Noneaker.

  • ICC - A technique to improve the performance of serial, matched-filter acquisition in direct-Sequence spread-spectrum packet radio communications
    IEEE International Conference on Communications 2003. ICC '03., 1
    Co-Authors: Arvind Swaminathan, D.l. Noneaker
    Abstract:

    In this paper we examine a simple method to improve the performance of serial, matched-filter acquisition indirect-Sequence spread-spectrum packet radio communications. Each packet transmission includes an acquisition Preamble, and the Preamble Sequence is changed at the boundaries of predefined time epochs based on a pseudorandom Sequence generator. It is shown in previous work that the presence of an IF filter and the characteristics of the AGC subsystem, lead to a probability of not acquiring that is a non-monotonic function of the signal-to-noise ratio if the acquisition algorithm uses a threshold-crossing detector with a fixed threshold. The acquisition algorithm presented in this paper employs an estimator to adaptively select the acquisition threshold. It is shown that this technique reduces the severity of the non-monotonicity and substantially improves the acquisition performance.

Philipp Zhang - One of the best experts on this subject based on the ideXlab platform.

  • Preamble design for non contiguous spectrum usage in cognitive radio networks
    Wireless Communications and Networking Conference, 2009
    Co-Authors: Shulan Feng, Heather Zheng, Haiguang Wang, Jinnan Liu, Philipp Zhang
    Abstract:

    Cognitive radios can significantly improve spectrum efficiency by using locally available spectrum. The efficiency, however, depends heavily on their transceiver design. In particular, being able to use non-contiguously aligned spectrum bands simultaneously is a critical requirement. Prior work in this area requires a control channel so that transmitter/receiver pairs can synchronize on their spectrum usage patterns. However, this approach can suffer from high cost and control congestion. In this paper, we propose an in-band solution for informing receivers the spectrum usage patterns. By judiciously designing packet Preambles, we embed the spectrum usage patterns in each data packet. Using the legacy 802.11 Preamble structure, we focus on choosing the appropriate Preamble Sequences to maintain reliable packet detection in the presence of noise and interference. We verify our design using simulation and show that it can lead to reliable packet transmissions comparable to those of contiguous spectrum usage. We also identify the impact of interference on our design and propose refinements to choose the Preamble Sequence using information on the interference.

  • WCNC - Preamble Design for Non-Contiguous Spectrum Usage in Cognitive Radio Networks
    2009 IEEE Wireless Communications and Networking Conference, 2009
    Co-Authors: Shulan Feng, Heather Zheng, Haiguang Wang, Jinnan Liu, Philipp Zhang
    Abstract:

    Cognitive radios can significantly improve spectrum efficiency by using locally available spectrum. The efficiency, however, depends heavily on their transceiver design. In particular, being able to use non-contiguously aligned spectrum bands simultaneously is a critical requirement. Prior work in this area requires a control channel so that transmitter/receiver pairs can synchronize on their spectrum usage patterns. However, this approach can suffer from high cost and control congestion. In this paper, we propose an in-band solution for informing receivers the spectrum usage patterns. By judiciously designing packet Preambles, we embed the spectrum usage patterns in each data packet. Using the legacy 802.11 Preamble structure, we focus on choosing the appropriate Preamble Sequences to maintain reliable packet detection in the presence of noise and interference. We verify our design using simulation and show that it can lead to reliable packet transmissions comparable to those of contiguous spectrum usage. We also identify the impact of interference on our design and propose refinements to choose the Preamble Sequence using information on the interference.

Yeong Jun Kim - One of the best experts on this subject based on the ideXlab platform.

  • A Preamble Sequence Design Techniqe for Efficient Beam ID Detection in Millimeter-Wave Cellular Systems
    IEEE Transactions on Vehicular Technology, 2016
    Co-Authors: Yeong Jun Kim, Dae Gen Han, Yong-soo Cho
    Abstract:

    The beam training protocol in millimeter-wave cellular systems requires a long processing time that is proportional to the product of the number of Tx beams, number of Rx beams, and number of neighbor base stations. In this paper, a Preamble design technique that can significantly reduce the processing time for beam training in an orthogonal-frequency-division-multiplexing-based cellular system is proposed by transmitting multiple beams with their corresponding Tx beam IDs (BIDs) and cell ID (CID). The Zadoff-Chu (ZC) Sequence, with its length given by a multiplication of two prime numbers, is proposed for an efficient CID and BID (CBID) search in a Preamble design. It is shown by computer simulation that the proposed Preamble design technique can obtain a 10- to 20-fold computational complexity gain in CBID detection and achieve a performance (0.1-dB signal-to-noise ratio shift) that is close to that of a ZC Sequence with a prime length.

  • Efficient Preamble Design Technique for Millimeter-Wave Cellular Systems with Beamforming.
    Sensors, 2016
    Co-Authors: Dae Geun Han, Yeong Jun Kim, Yong-soo Cho
    Abstract:

    The processing time for beam training in millimeter-wave (mmWave) cellular systems can be significantly reduced by a code division multiplexing (CDM)-based technique, where multiple beams are transmitted simultaneously with their corresponding Tx beam IDs (BIDs) in the Preamble. However, mmWave cellular systems with CDM-based Preambles require a large number of cell IDs (CIDs) and BIDs, and a high computational complexity for CID and BID (CBID) searches. In this paper, a new Preamble design technique that can increase the number of CBIDs significantly is proposed, using a Preamble Sequence constructed by a combination of two Zadoff-Chu (ZC) Sequences. An efficient technique for the CBID detection is also described for the proposed Preamble. It is shown by simulations using a simple model of an mmWave cellular system that the proposed technique can obtain a significant reduction in the complexity of the CBID detection without a noticeable performance degradation, compared to the previous technique.

  • ICUFN - Preamble design technique for millimeter-wave cellular systems using Zadoff-Chu Sequences
    2016 Eighth International Conference on Ubiquitous and Future Networks (ICUFN), 2016
    Co-Authors: Dae Gen Han, Yeong Jun Kim, Yong-soo Cho
    Abstract:

    In this paper, a new Preamble design technique that can increase the number of cell IDs (CIDs) and beam IDs (BIDs) significantly is proposed, using a Preamble Sequence constructed by a combination of two Zadoff-Chu (ZC) Sequences. An efficient technique for the CID and BID (CBID) detection is also described for the proposed Preamble. It is shown by simulations using a simple model of an mmWave cellular system that the proposed technique can obtain a significant reduction in the complexity of the CBID detection without a noticeable performance degradation, compared to the previous technique.