Notification:
We are currently experiencing intermittent issues impacting performance. We apologize for the inconvenience.
By Topic

Ultra Wideband Systems, 2004. Joint with Conference on Ultrawideband Systems and Technologies. Joint UWBST & IWUWBS. 2004 International Workshop on

Date 18-21 May 2004

Filter Results

Displaying Results 1 - 25 of 105
  • Chirp UWB system with software defined receiver for industrial mobile ranging and autonomous control

    Publication Year: 2004 , Page(s): 381 - 385
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (421 KB) |  | HTML iconHTML  

    In this paper, a chirp UWB scheme deployed for both ranging and communication is proposed. Its target application is for industrial mobile ranging and autonomous control that require very high reliability. To construct both ranging and communication circuit hardware, the SDR technique is employed as a receiver platform for this chirp UWB system. Since the chirp modulation scheme is very simple and presents a very stable communication medium, it promises that the proposed system has the high performance and robustness necessary for industrial applications. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Frequency hopping ultra wideband inter-vehicle radar system using chirp waveforms

    Publication Year: 2004 , Page(s): 386 - 390
    Cited by:  Papers (11)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (341 KB) |  | HTML iconHTML  

    In this paper we propose a inter-vehicle UWB ranging system using chirp waveforms instead of the conventional UWB-IR ranging system that uses modulated Gaussian pulses. In the proposed system, the transmitted signal consists of a linear combination of chirp signals with the same time duration but different frequency bands. It is assumed that the channel model of the inter-vehicle communication system is a two-path channel model. The proposed system and conventional UWB-IR ranging system is evaluated in such a two-path channel model. The proposed system achieves better performance. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Robust noncoherent receiver exploiting UWB channel properties

    Publication Year: 2004 , Page(s): 156 - 160
    Cited by:  Papers (64)  |  Patents (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (451 KB) |  | HTML iconHTML  

    Most UWB radio receivers discussed in the literature are coherent receivers, which can offer high signal sensitivity and support high data rates but require precise timing clock recovery and complex RAKE structures. For UWB radio systems requiring only lower data throughput, noncoherent receiver architectures offer a good performance-complexity tradeoff. In this paper, we describe a noncoherent receiver for 2PPM UWB signals. The key design parameter, the duration of signal integration, can be chosen such that a target BER is achieved for each element of a preselected set of channel realizations. Although the proposed receiver works without channel state information and complex RAKE frontend, its performance compares favorably with that of a coherent 2PAM RAKE receiver of low order. The simple noncoherent receiver exploits most of the multipath diversity offered by the channel and is robust to clock timing errors. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Modulation and hopping using modified Hermite pulses for UWB communications

    Publication Year: 2004 , Page(s): 336 - 340
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (345 KB) |  | HTML iconHTML  

    As the communication system for a new indoor short distance radio-communication for wireless personal area networks (WPAN), the ultra wideband (UWB) system is examined towards standardization. In such an examination, the UWB system uses limited bandwidth and transmitted power in order to avoid interference with other systems. The possibility of realization, with such as the multiband type, which uses a subcarrier, is higher than the system which does not use a subcarrier, like the impulse radio (IR) system considered conventionally. The "modified Hermite pulse", as proposed for application to the IR system, is modulated, and the application to UWB of the "modulated and modified Hermite pulse", improved so that only a desired bandwidth might be occupied, is proposed. Furthermore, with respect to the characteristics and the performance of the waveform, it is evaluated using computer simulations, and is shown to excel in the BER characteristic as compared with a multiband-FHTH system. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • ZCD-UWB system using enhanced ZCD codes

    Publication Year: 2004 , Page(s): 371 - 375
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (378 KB) |  | HTML iconHTML  

    We propose a ZCD-UWB using zero correlation duration (ZCD) code for direct sequence-ultra wideband (DS-UWB). Then, we introduce a class of new ternary ZCD spreading codes with aperiodic and periodic ZCD property for ZCD-UWB and CDMA applications. After constructing a mathematical model for ZCD-UWD wireless communication system, we present theoretical bit error rate (BER) performance of the system. By using computer simulation, we verify the proposed system having high system capacity and superior performance to the Walsh code-based DS-UWB systems in multipath and in multiple access environments. Finally, we show that the proposed system can remove the interference signal perfectly without employing complicated hardware such as multiuser detection (MUD) or other interference cancellation techniques. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Evaluation of selective RAKE receiver in direct sequence ultra wideband communications in the presence of interference

    Publication Year: 2004 , Page(s): 221 - 225
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (404 KB) |  | HTML iconHTML  

    Performance of a selective RAKE (SRAKE) receiver is evaluated for direct sequence ultra wideband (DS-UWB) communications considering an independent Rayleigh channel having exponentially decaying power delay profile (PDP). BEP performance is shown. The results obtained are compared with similar results in a channel having flat PDP. Assumption of a flat PDP (as was previously made in DS-SS) is found to predict the optimum spreading bandwidth to be lower and suboptimum operating performance beyond optimum spreading bandwidth to be severely worse than what is achievable in a real channel with an SRAKE receiver having fixed number of combined paths. Optimum spreading bandwidth for SRAKE in a channel having exponentially decaying PDP is shown to be much larger than the one in a channel having flat PDP. This is specifically good news for UWB communication. Effects of partial band interference have also been considered. Interference is found to be less effective in case of exponentially decaying PDP. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Multiple access performance of UWB M-ary impulse radio systems with diversity reception

    Publication Year: 2004 , Page(s): 346 - 350
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (388 KB) |  | HTML iconHTML  

    Impulse radio (IR) is based on ultra-wideband (UWB) time-hopping spread spectrum technology. The influence of temporal and spatial diversities on the multiple access performance of M-ary pulse position modulation (PPM) IR systems in multipath environments is analyzed. We investigate the used of an antenna array at the receiver to improve the multiple access performance of the system in terms of the number of active users supported by the system for a given bit error rate and bit transmission rate. Numerical results show that the bit error rate performance and multiple access capacity of the M-ary IR system can be improved by increasing the number of antenna array elements and selected multipaths at the receiver. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Performance studies of a multi-band OFDM system using a simplified LDPC code

    Publication Year: 2004 , Page(s): 376 - 380
    Cited by:  Papers (7)  |  Patents (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (441 KB) |  | HTML iconHTML  

    Ultra-wideband (UWB) is a promising radio technology for networks delivering extremely high data rates at short ranges. Multi-band orthogonal frequency division multiplexing (MB-OFDM) is a suitable solution to implement high speed data in ultra wideband spectrum by dividing the available spectrum into multiple bands. MB-OFDM achieves adaptability as well as high performance, low-power and low-cost characteristics through the usage of OFDM. Due to the importance of error correcting codes for OFDM systems, it is essential to employ a powerful error correcting code for the MB-OFDM system to improve the performance. Recently, low-density parity-check (LDPC) code has attracted great attention because it achieves bit error rate near to the Shannon limit. In this paper, we design and evaluate the performance of the MB-OFDM system using LDPC code. In order to simplify the implementation of the LDPC encoder and decoder, we introduce a joint code and decoder design approach to construct a class of (3, k)-regular LDPC code which exactly fits to a partly parallel decoder implementation. The simulations show that the performance of such a simplified LDPC coded MB-OFDM system is better than that of a convolutional coded MB-OFDM system, and is very close to that of the conventional LDPC coded MB-OFDM system. The implementation complexity of the simplified LDPC code is carefully examined subsequently in the paper. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A PPM Gaussian monocycle transmitter for ultra-wideband communications

    Publication Year: 2004 , Page(s): 130 - 134
    Cited by:  Papers (28)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (339 KB) |  | HTML iconHTML  

    A Gaussian pulse generator incorporating a pulse position modulator for use in an impulse radio ultrawideband system is described. The pulse generator is preceded by a programmable pulse position modulator and comprises a cascade of complex first-order systems, which, in turn, are made up of differential pairs employing partial positive feedback. The resulting PPM Gaussian pulse generator is designed in IBM 0.18 μm Bi-CMOS IC technology. Simulations predict the correct operation of the circuit for supply voltages of 1.8 V and a power consumption of 30 mW. The output monocycle indeed approximates a Gaussian monocycle, having a pulse duration of about 250 ps. Proper modulation of the pulse in time is confirmed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Performance evaluation of RAKE reception of ultra wideband signals over multipath channels from energy capture perspective

    Publication Year: 2004 , Page(s): 231 - 235
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (432 KB) |  | HTML iconHTML  

    In this paper, we derive the SEP for time-hopping M-ary PPM (TH-MPPM) UWB communication systems as a function of captured SNR per symbol and simplify the results for TH-BPSK. For the TH-MPPM system, we incorporate the effect of modulation index (δ) on SEP. The results obtained give us way to evaluate the performance of RAKE reception of UWB signals in dense multipath channels from the energy capture perspective. We present more general results that can be applied for verification of RAKE implementations. We present simulation results using IEEE 802.15.3a UWB channel models for various pulsewidths. We evaluate the performance of optimum and ordinary all RAKE (ARAKE) and selective RAKE (SRAKE) receivers in different channel models (CM1 to CM3). We compare relative costs of simplifying various RAKE complexities. Conditioned on some parameters, we present an optimum pulse width for UWB communications while SRAKE is employed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A novel delay locked loop for UWB-IR

    Publication Year: 2004 , Page(s): 273 - 277
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (317 KB) |  | HTML iconHTML  

    The paper proposes a novel delay locked loop (DLL) for an ultra wideband-impulse radio (UWB-IR) system with time hopping/spread spectrum (TH/SS), and presents its characteristics. The DLL circuit adopts a discriminator composed of two correlators with arbitrary time delay. Jitter, lose lock time, and bit error rate (BER) performances are evaluated by computer simulations. The results show that these performances of the proposed method are superior to those of a conventional method. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A novel modification method for IEEE802.15.3a channel model [UWB]

    Publication Year: 2004 , Page(s): 86 - 90
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (331 KB) |  | HTML iconHTML  

    Based on the all-rake receiver theory, a modification method for UWB multipath channel models is proposed. In accordance with the UWB pulse shaping scheme, it can modify the IEEE802.15.3a multipath channel model into a tapped-delay-line channel model with specific center frequency and multipath resolution. The modified channel model provides a design reference and simplifies the system analysis and simulation. As an example, the modification for a typical UWB pulse has been done, and the statistical characteristics of the modified channel model have been analyzed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A fast and reliable acquisition scheme for detecting ultra wide-band impulse radio signals in the presence of multi-path and multiple access interference

    Publication Year: 2004 , Page(s): 106 - 110
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (417 KB) |  | HTML iconHTML  

    Ultra wide-band time-hopping impulse radio (UWB-TH-IR) creates a UWB signal by the continuous repetition of sub-ns wide bandwidth pulses which are pseudo randomly time hopped. A simple receiver, consisting of one or more one-shot correlators triggered at the precise moment the received pulse arrives at the receiver, can be used to detect the signal. This structure makes it necessary to initially synchronise to the incoming signals pseudo random time-hopping code. The combination of the low duty cycle waveform and the presence of a pseudo random time-hopping code can make the search space large, resulting in long synchronisation times. This paper proposes a so called quick search (QS) method which significantly reduces the search time by making more efficient use of the context of each observation. When compared to the exhaustive search (ES) method, the algorithm proposed here exhibits an acceptable degradation in detection performance and can reduce the search time by a factor equal to the code length. Performance is bench marked against the ES method along with the linear search (LS), random search (RS) and binary reverse search (BRS) thresholded algorithms. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Orthogonal on-off UWB signaling scheme with one-shot linear decorrelating detector over Nakagami-m fading channel

    Publication Year: 2004 , Page(s): 101 - 105
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (365 KB) |  | HTML iconHTML  

    Recently, ultra wide band (UWB) techniques have drawn much attention from either the academic world or industry. A convenient signaling scheme, termed orthogonal on-off UWB (O3 UWB), along with a simple one-shot linear decorrelating detector (LDD), is proposed in this paper. It is a technique for near-far resistant detection in asynchronous UWB systems. The temporally adjacent bits from different users in the receiver are decoupled by using the on-off signaling, and the data rate is maintained, with no increase in transmission rate, by adopting an orthogonal structure. In this paper, we study the system performance over a Nakagami-m fading channel. Numerical results show that O3 UWB LDD can offer a good near-far resistant property over a Nakagami-m fading channel. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Low-complexity ultrawideband transceiver with compatibility to multiband-OFDM

    Publication Year: 2004 , Page(s): 151 - 155
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (463 KB) |  | HTML iconHTML  

    We present a low-complexity transceiver for ultrawideband communications with moderate (1-15 Mbit/s) data rate. This transceiver is based on time-frequency-interleaved frequency-shift-keying (TF-FSK), and shows a high degree of compatibility with multiband-OFDM, the currently envisioned standard for high-data-rate (>100 Mbit/s) UWB communications. We show that for dual-mode devices, the major part of the multiband-OFDM transceiver can be reused for the TF-FSK transceiver. We also study the performance of this transceiver in (standardized) UWB channels, and find that, depending on the data rate, coverage ranges of up to 30 m (with LOS connection) are possible. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Low noise amplifier with center frequency hopping for an MB-OFDM UWB receiver

    Publication Year: 2004 , Page(s): 420 - 423
    Cited by:  Papers (4)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (333 KB) |  | HTML iconHTML  

    We describe a real-time center frequency hopping scheme in which the resonant frequency of an LC load is changed by switching binary weighted capacitors and where switching noise is canceled with compensation transistors and CML buffers. Simulation results employing 0.18-μm CMOS technology have verified that the center frequency is changed within 3 ns. A peak power gain of 17 dB and noise figure of 3.3 dB were simulated. This scheme is applicable to sub-100-nm reconfigurable radios. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Performance comparison of UWB-IR using RAKE receivers in UWB channel models

    Publication Year: 2004 , Page(s): 226 - 230
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (425 KB) |  | HTML iconHTML  

    We evaluate the performance of the ultra wideband impulse radio with Walsh Hadamard BPSK (UWB-IR with WH-BPSK) using RAKE receivers in two channel models. The first channel model (J. Foerster and Q. Li (2002)) is referred to as an (A) model. The measurements characterize the channel over the frequency range of 2-8 GHz using 0.167 ns baseband pulses. The amplitudes of multipath are modeled with the lognormal fading distribution. The second channel model (D. Cassioli and M. Z. Win (2002)) is referred to as a (B) model, The measurements characterize the channel over the frequency range of 1.5-3 GHz using 2.0 ns baseband pulses. The amplitudes of multipath are modeled with the Nakagami distribution. We evaluate the signal to noise ratio (SNR) distribution of the RAKE combining output and the bit error rate (BER) of UWB-IR with WH-BPSK using the partial RAKE (PRAKE) receiver and the selective RAKE (SRAKE) receiver for the given number of fingers in the two channel models. We show that using the PRAKE receiver, the UWB-IR with WH-BPSK in the (B) model can achieve a better BER than that in the (A) model when the number of fingers is small (i.e., L = 2, 10) and vice versa when the number of fingers is large (i.e., L ≥ 50). We also show that using the SRAKE receiver, the UWB-IR with WH-BPSK in the (A) model can achieve the better BER than that in the (B) model for any L. Therefore, we confirm that the performance of the UWB-IR using the RAKE receivers, particularly, the PRAKE receiver, depends largely on the channel model. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Through-material propagation characteristic and time resolution of UWB signal

    Publication Year: 2004 , Page(s): 71 - 75
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (402 KB) |  | HTML iconHTML  

    Nice penetration capability and fine time resolution have been considered as important properties of the ultra-wideband (UWB) signal. The characteristic of UWB through-material propagation needs to be reevaluated since the FCC-defined spectrum mask does not match the traditional impulse radio signal spectrum. A set of frequency domain measurement results conducted for this purpose are presented. The UWB ambiguity function is defined and evaluated to illustrate the time resolution UWB signal; timing issues pertinent to the system design are discussed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Implementation of a multi-tone signal generator for ultra wideband transceiver

    Publication Year: 2004 , Page(s): 263 - 267
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (428 KB) |  | HTML iconHTML  

    A method of generating multiple carrier signal tones for a wideband QPSK modulator is developed. Multiple wideband tones spanning over several GHz bandwidths are generated using a mixture of single sideband (SSB) mixers and a band selection switching network. Compared with traditional ultra-wideband (UWB) communication systems, the proposed method requires relatively narrowband components only and can be directly applied for implementing a multiband ultra-wideband (UWB) communication system. A full UWB radio block is implemented using off-the-shelf discrete components and tested. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Carrier-less, single and multi-carrier UWB radio technology

    Publication Year: 2004 , Page(s): 192 - 196
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (420 KB) |  | HTML iconHTML  

    The Federal Communications Commission (FCC) has opened up 7,500 MHz of spectrum (3.1-10.6 GHz) for the unlicensed use of ultra wideband (UWB) products. UWB is a promising radio technology for networks delivering extremely high data rates at short ranges. The main focus of the paper is introducing the carrier-less UWB system that we designed in our demonstration platform, including the system architecture, TH-PPM technique and the candidates of the pulse shape. Then the single and multi-carrier UWB radio technologies are introduced and the different characteristics of the three solutions are studied and compared. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Characteristics of planar and orthogonal planar monopole antenna with dual frequency for UWB system

    Publication Year: 2004 , Page(s): 171 - 175
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (366 KB) |  | HTML iconHTML  

    Since the UWB system covers from 3.1 to 10.6 GHz, it is necessary to suppress the interference from other systems using some of the 3.1-10.6 GHz frequency band. Two types of novel planar monopole dual frequency antennas, which consist of two connected elements, are presented. These antennas are like slitted planar monopole antennas, and one of the presented antennas is the novel orthogonal planar monopole antenna. The proposed planar and orthogonal planar monopole antennas' structures have dual frequency and broad bandwidth characteristics at both resonant frequencies. The return loss level at the suppressed frequency between both resonant frequencies is almost 0 dB. The radiation patterns at all frequency ranges are almost omnidirectional in the horizontal plane. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • BER performance of pulsed UWB system in the presence of colored timing jitter

    Publication Year: 2004 , Page(s): 293 - 297
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (424 KB) |  | HTML iconHTML  

    Ultra wideband systems impose a high demand on the jitter performance of the system clock. The effects of white Gaussian jitter have been considered in the literature. However, in practical systems, the system clock exhibits colored timing jitter. We investigate the BER performance of a binary pulse position modulation (PPM) single-user UWB communication system subjected to both white and colored clock timing jitters. Using typical simulation parameters found in the literature, we found that colored jitter degrades the BER performance more than white jitter, and the extent of BER degradation increases as the jitter becomes more correlated. The BER performance curve in the white jitter for the case where multiple chips are used to represent a single bit is analytically derived and it agrees with the simulation results. The theoretical BER performance in the colored jitter case is found to be lower bounded by that of the white jitter case and upper bounded by the BER performance for the case where a single chip is used to represent a single bit, agreeing with the simulation results. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Multiuser interference and inter-frame interference in UWB transmitted reference systems

    Publication Year: 2004 , Page(s): 96 - 100
    Cited by:  Papers (32)  |  Patents (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (401 KB) |  | HTML iconHTML  

    In transmitted reference ultra-wideband (TR-UWB) systems and differential transmitted reference (DTR-UWB) systems, the performance is, besides noise, determined by interference among pulses due to the dispersive multipath radio channel (interframe interference). The multiple access interference is also heavily influenced by multipath propagation. As a first step towards the analysis and optimization of such systems, this paper analyzes statistically the response of the pulse-pair correlators, including integrate and dump circuits which are the basic building blocks of TR-UWB receivers, to desired and un-desired pulse-pairs. Results are given in terms of basic channel parameters like RMS delay spread and Ricean K-factor. As an example for the application of our analysis, we present a novel multiuser DTR-UWB system. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Theoretical limit on two dimensional generalized complementary orthogonal sequence set with zero correlation zone in ultra wideband communications

    Publication Year: 2004 , Page(s): 197 - 201
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (282 KB) |  | HTML iconHTML  

    The application of two dimensional (2D) complementary sequences in ultra wideband (UWB) communication systems has brought a new opportunity for such systems' development. To binary, ternary or polyphase two-dimensional sequence sets, the concept of 2D complementary sequences is generalized to a 2D generalized complementary orthogonal sequence set (GCOSS) with zero correlation zone (ZCZ); a novel lower bound for such a sequence set is derived and presented. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A design of tunable UWB filters

    Publication Year: 2004 , Page(s): 424 - 428
    Cited by:  Papers (9)  |  Patents (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (383 KB) |  | HTML iconHTML  

    A novel design method is proposed for UWB filters using a ring resonator structure with a stub. A five stage UWB filter with 86.6% relative bandwidth is fabricated based on a design method which shows an excellent performance, i.e. low insertion loss of 0.58 dB and flat group delay of 1.6 nsec. We also extend the design method to the one for a wide range tunable filter. Simulated results show that more than 40% tunable range can be obtained with a single capacitor for each ring resonator. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.