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363 Publications
2007 | Conference Paper | LibreCat-ID: 1840
Multiple-Access Relay Channel with Network Coding and Non-Ideal Source-Relay Channels
D.H. Woldegebreal, H. Karl, in: 2007 4th International Symposium on Wireless Communication Systems, IEEE, 2007.
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D.H. Woldegebreal, H. Karl, in: 2007 4th International Symposium on Wireless Communication Systems, IEEE, 2007.
2007 | Conference Paper | LibreCat-ID: 1842
Optimizing sleeping intervals in preamble sampling MAC for WSNs
H. Karl, in: Communication in Distributed Systems (KiVS), 2007 ITG-GI Conference, Bern / Switzerland, 2007.
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H. Karl, in: Communication in Distributed Systems (KiVS), 2007 ITG-GI Conference, Bern / Switzerland, 2007.
2007 | Journal Article | LibreCat-ID: 830
Investigation of multicast-based mobility support in all-IP cellular networks
A. Festag, H. Karl, A. Wolisz, Wireless Communications and Mobile Computing (2007) 319--339.
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A. Festag, H. Karl, A. Wolisz, Wireless Communications and Mobile Computing (2007) 319--339.
2007 | Conference Paper | LibreCat-ID: 831
WASP - Wirelessly Accessible Sensor Populations: A Project Overview
P. van der Stok, H. Karl, F. De Ambroggi, J. Decotignie, F. Siegemund, K. Lokhorst, M. Hellenschmidt, in: Constructing Ambient Intelligence - AmI 2007 Workshops Darmstadt, Germany, November 7-10, 2007 Revised Papers, 2007, pp. 426--429.
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P. van der Stok, H. Karl, F. De Ambroggi, J. Decotignie, F. Siegemund, K. Lokhorst, M. Hellenschmidt, in: Constructing Ambient Intelligence - AmI 2007 Workshops Darmstadt, Germany, November 7-10, 2007 Revised Papers, 2007, pp. 426--429.
2007 | Conference Paper | LibreCat-ID: 832
Outage probability analysis of cooperative transmission protocols without and with network coding: inter-user channels based comparison
D. H. Woldegebreal, S. Valentin, H. Karl, in: Proceedings of the 10th International Symposium on Modeling Analysis and Simulation of Wireless and Mobile Systems, MSWiM 2007, Chania, Crete Island, Greece, October 22-26, 2007, 2007, pp. 36--44.
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D. H. Woldegebreal, S. Valentin, H. Karl, in: Proceedings of the 10th International Symposium on Modeling Analysis and Simulation of Wireless and Mobile Systems, MSWiM 2007, Chania, Crete Island, Greece, October 22-26, 2007, 2007, pp. 36--44.
2007 | Conference Paper | LibreCat-ID: 833
Traffic-Aware Asymmetric Cooperation Diversity for Media Streaming in Wireless Networks
S. Valentin, H. von Malm, H. Karl, in: Proceedings of the IEEE 18th International Symposium on Personal, Indoor and Mobile Radio Communications, PIMRC 2007, 3-7 September 2007, Athens, Greece, 2007, pp. 1--6.
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S. Valentin, H. von Malm, H. Karl, in: Proceedings of the IEEE 18th International Symposium on Personal, Indoor and Mobile Radio Communications, PIMRC 2007, 3-7 September 2007, Athens, Greece, 2007, pp. 1--6.
2007 | Conference Paper | LibreCat-ID: 834
Integrating multiuser dynamic OFDMA into IEEE 802.11a and prototyping it on a real-time software-defined radio testbed
H. S. Lichte, S. Valentin, F. Eitzen, M. Stege, C. Unger, H. Karl, in: 3rd International ICST Conference on Testbeds and Research Infrastructures for the Development of Networks and Communities, TridentCom 2007, Orlando, Florida, USA, May 21-23 2007, 2007, pp. 1--9.
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H. S. Lichte, S. Valentin, F. Eitzen, M. Stege, C. Unger, H. Karl, in: 3rd International ICST Conference on Testbeds and Research Infrastructures for the Development of Networks and Communities, TridentCom 2007, Orlando, Florida, USA, May 21-23 2007, 2007, pp. 1--9.
2007 | Conference Paper | LibreCat-ID: 835
Effect of User Mobility in Coded Cooperative Systems with Joint Partner and Cooperation Level Selection
S. Valentin, H. Karl, in: IEEE Wireless Communications and Networking Conference, WCNC 2007, Hong Kong, China, 11-15 March, 2007, 2007, pp. 896--901.
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S. Valentin, H. Karl, in: IEEE Wireless Communications and Networking Conference, WCNC 2007, Hong Kong, China, 11-15 March, 2007, 2007, pp. 896--901.
2007 | Conference Paper | LibreCat-ID: 836
Multi-rate Relaying for Performance Improvement in IEEE 802.11 WLANs
L. Marie Feeney, B. Cetin, D. Hollos, M. Kubisch, S. Mengesha, H. Karl, in: Wired/Wireless Internet Communications, 5th International Conference, WWIC 2007, Coimbra, Portugal, May 23-25, 2007, Proceedings, 2007, pp. 201--212.
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L. Marie Feeney, B. Cetin, D. Hollos, M. Kubisch, S. Mengesha, H. Karl, in: Wired/Wireless Internet Communications, 5th International Conference, WWIC 2007, Coimbra, Portugal, May 23-25, 2007, Proceedings, 2007, pp. 201--212.
2007 | Conference Paper | LibreCat-ID: 1015
Analyzing the effect of asymmetric mobility and channel configurations on the outage performance of coded cooperative systems
S. Valentin, H. Karl, in: Proc. of the European Wireless Conference (EW), 2007.
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S. Valentin, H. Karl, in: Proc. of the European Wireless Conference (EW), 2007.
2007 | Journal Article | LibreCat-ID: 1018
Implementing cooperative wireless networks
S. Valentin, H.S. Lichte, H. Karl, S. Simoens, G. Vivier, J. Vidal, A. Agustin, Cognitive Wireless Networks (2007) 155--178.
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S. Valentin, H.S. Lichte, H. Karl, S. Simoens, G. Vivier, J. Vidal, A. Agustin, Cognitive Wireless Networks (2007) 155--178.
2006 | Report | LibreCat-ID: 2518
Evaluating the GNU Software Radio platform for wireless testbeds
S. Valentin, H. von Malm, H. Karl, Evaluating the GNU Software Radio Platform for Wireless Testbeds, 2006.
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S. Valentin, H. von Malm, H. Karl, Evaluating the GNU Software Radio Platform for Wireless Testbeds, 2006.
2006 | Conference Paper | LibreCat-ID: 2523
Cooperative wireless networking beyond store-and-forward: Perspectives for PHY and MAC design
S. Valentin, H.S. Lichte, H. Karl, G. Vivier, S. Simoens, J. Vidal, A. Agustin, I. Aad, in: 2006.
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S. Valentin, H.S. Lichte, H. Karl, G. Vivier, S. Simoens, J. Vidal, A. Agustin, I. Aad, in: 2006.
2006 | Conference Paper | LibreCat-ID: 2526
An IEEE 802.21-based Universal Information Service
C. Dannewitz, S. Berg, H. Karl, in: Proc. of the Wireless World Research Forum Meeting , 2006.
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C. Dannewitz, S. Berg, H. Karl, in: Proc. of the Wireless World Research Forum Meeting , 2006.
2006 | Journal Article | LibreCat-ID: 837
A perceptual quality model intended for adaptive VoIP applications
C. Hoene, H. Karl, A. Wolisz, Int. J. Communication Systems (2006) 299--316.
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C. Hoene, H. Karl, A. Wolisz, Int. J. Communication Systems (2006) 299--316.
2006 | Journal Article | LibreCat-ID: 838
Performance analysis of dynamic OFDMA systems with inband signaling
J. Gross, H.-}Florian Geerdes, H. Karl, A. Wolisz, IEEE Journal on Selected Areas in Communications (2006) 427--436.
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J. Gross, H.-}Florian Geerdes, H. Karl, A. Wolisz, IEEE Journal on Selected Areas in Communications (2006) 427--436.
2006 | Journal Article | LibreCat-ID: 839
A Distributed End-to-End Reservation Protocol for IEEE 802.11-Based Wireless Mesh Networks
E. Carlson, C. Prehofer, C. Bettstetter, H. Karl, A. Wolisz, IEEE Journal on Selected Areas in Communications (2006) 2018--2027.
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E. Carlson, C. Prehofer, C. Bettstetter, H. Karl, A. Wolisz, IEEE Journal on Selected Areas in Communications (2006) 2018--2027.
2006 | Conference Paper | LibreCat-ID: 840
Wireless Sensor Networks
F. Mattern, H. Karl, K. Römer, in: K. R{\"{o}}mer, H. Karl, F. Mattern (Eds.), Third European Workshop, {EWSN} 2006, Zurich, Switzerland, February 13-15, 2006, Proceedings, 2006.
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F. Mattern, H. Karl, K. Römer, in: K. R{\"{o}}mer, H. Karl, F. Mattern (Eds.), Third European Workshop, {EWSN} 2006, Zurich, Switzerland, February 13-15, 2006, Proceedings, 2006.
2005 | Conference Paper | LibreCat-ID: 1843
Channel-Adaptive Schedulers with State-of-the-Art Channel Predictors
A. Aguiar, A. Wolisz, H. Lederer, H. Karl, in: Proceedings of the 11th European Wireless Conference 2005, 2005.
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A. Aguiar, A. Wolisz, H. Lederer, H. Karl, in: Proceedings of the 11th European Wireless Conference 2005, 2005.
2005 | Book | LibreCat-ID: 841
Protocols and architectures for wireless sensor networks
H. Karl, A. Willig, Protocols and Architectures for Wireless Sensor Networks, 2005.
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H. Karl, A. Willig, Protocols and Architectures for Wireless Sensor Networks, 2005.
2005 | Journal Article | LibreCat-ID: 842
Does Multi-Hop Communication Reduce Electromagnetic Exposure?
J.-P. Ebert, D. Hollos, H. Karl, M. Löbbers, Comput. J. (2005) 72--83.
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J.-P. Ebert, D. Hollos, H. Karl, M. Löbbers, Comput. J. (2005) 72--83.
2005 | Journal Article | LibreCat-ID: 843
Analysis and performance evaluation of the EFCM common congestion controller for TCP connections
M. Savoric, H. Karl, M. Schläger, T. Poschwatta, A. Wolisz, Computer Networks (2005) 269--294.
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M. Savoric, H. Karl, M. Schläger, T. Poschwatta, A. Wolisz, Computer Networks (2005) 269--294.
2005 | Journal Article | LibreCat-ID: 844
A study of impact of inband signalling and realistic channel knowledge for an example dynamic OFDM-FDMA system
J. Gross, S. Valentin, H. Karl, A. Wolisz, European Transactions on Telecommunications (2005) 37--49.
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J. Gross, S. Valentin, H. Karl, A. Wolisz, European Transactions on Telecommunications (2005) 37--49.
2005 | Journal Article | LibreCat-ID: 845
Drahtlose Sensornetze
H. Karl, T. Lentsch, H. Ritter, Praxis Der Informationsverarbeitung Und Kommunikation (2005) 66--67.
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H. Karl, T. Lentsch, H. Ritter, Praxis Der Informationsverarbeitung Und Kommunikation (2005) 66--67.
2005 | Journal Article | LibreCat-ID: 846
Data Transport Reliability in Wireless Sensor Networks. A Survey of Issues and Solutions
A. Willig, H. Karl, Praxis Der Informationsverarbeitung Und Kommunikation (2005) 86--92.
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A. Willig, H. Karl, Praxis Der Informationsverarbeitung Und Kommunikation (2005) 86--92.
2005 | Conference Paper | LibreCat-ID: 847
Using energy where it counts: protecting important messages in the link layer
A. Kopke, H. Karl, M. Lobbers, in: Wireless Sensor Networks, Second European Workshop, EWSN 2005, Istanbul, Turkey, January 31 - February 2, 2005, Proceedings, 2005, pp. 226--235.
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A. Kopke, H. Karl, M. Lobbers, in: Wireless Sensor Networks, Second European Workshop, EWSN 2005, Istanbul, Turkey, January 31 - February 2, 2005, Proceedings, 2005, pp. 226--235.
2005 | Book Chapter | LibreCat-ID: 848
Ad Hoc Networks
H. Karl, in: The Industrial Information Technology Handbook, 2005, pp. 1--16.
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H. Karl, in: The Industrial Information Technology Handbook, 2005, pp. 1--16.
2005 | Conference Paper | LibreCat-ID: 1013
Adaptive scheduling for heterogeneous traffic flows in cellular wireless OFDM-FDMA systems
S. Valentin, J. Gross, H. Karl, A. Wolisz, in: 10th IFIP International Conference on Personal Wireless Communications/PWC’05, Comar, France, 2005, 2005.
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S. Valentin, J. Gross, H. Karl, A. Wolisz, in: 10th IFIP International Conference on Personal Wireless Communications/PWC’05, Comar, France, 2005, 2005.
2005 | Journal Article | LibreCat-ID: 1378
A study of impact of inband signalling and realistic channel knowledge for an example dynamic OFDM-FDMA system
J. Gross, S. Valentin, H. Karl, A. Wolisz, European Transactions on Telecommunications 16 (2005) 37–49.
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J. Gross, S. Valentin, H. Karl, A. Wolisz, European Transactions on Telecommunications 16 (2005) 37–49.
2004 | Conference Paper | LibreCat-ID: 2529
Consensus in WSN – Identifying critical protocol mechanisms
A. Köpke, H. Karl, A. Wolisz, in: GI / ITG Fachgespräche Drahtlose Sensornetzwerke, 2004.
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A. Köpke, H. Karl, A. Wolisz, in: GI / ITG Fachgespräche Drahtlose Sensornetzwerke, 2004.
2004 | Conference Paper | LibreCat-ID: 1911
Channel Adaptive Techniques in the Presence of Channel Prediction Inaccuracy
A. Aguiar, H. Karl, A. Wolisz, in: Proceedings of European Wireless 2004, Barcelona / Spain , 2004.
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A. Aguiar, H. Karl, A. Wolisz, in: Proceedings of European Wireless 2004, Barcelona / Spain , 2004.
2004 | Journal Article | LibreCat-ID: 850
Cross-layer optimization of OFDM transmission systems for MPEG-4 video streaming
J. Gross, J. Klaue, H. Karl, A. Wolisz, Computer Communications (2004) 1044--1055.
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J. Gross, J. Klaue, H. Karl, A. Wolisz, Computer Communications (2004) 1044--1055.
2004 | Journal Article | LibreCat-ID: 851
Ambient networks: An architecture for communication networks beyond 3G
N. Niebert, A. Schieder, H. Abramowicz, G. Malmgren, J. Sachs, U. Horn, C. Prehofer, H. Karl, IEEE Wireless Communications (2004) 14--22.
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N. Niebert, A. Schieder, H. Abramowicz, G. Malmgren, J. Sachs, U. Horn, C. Prehofer, H. Karl, IEEE Wireless Communications (2004) 14--22.
2004 | Conference Paper | LibreCat-ID: 852
Improving the Energy Efficiency of Directed Diffusion Using Passive Clustering
V. Handziski, A. Köpke, H. Karl, C. Frank, W. Drytkiewicz, in: Wireless Sensor Networks, First European Workshop, EWSN 2004, Berlin, Germany, January 19-21, 2004, Proceedings, 2004, pp. 172--187.
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V. Handziski, A. Köpke, H. Karl, C. Frank, W. Drytkiewicz, in: Wireless Sensor Networks, First European Workshop, EWSN 2004, Berlin, Germany, January 19-21, 2004, Proceedings, 2004, pp. 172--187.
2004 | Conference Paper | LibreCat-ID: 853
Research Challenges in Mobility and Moving Networks: An Ambient Networks View
V. Typpö, J. Eisl, J. Höller, R. Agüero, H. Karl, in: Broadband Satellite Comunication Systems and the Challenges of Mobility - IFIP TC6 Workshops on Broadband Satellite Communication Systems and Challenges of Mobility, World Computer Congress, August 22-27, 2004, Toulouse, France, 2004, pp. 145--155.
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V. Typpö, J. Eisl, J. Höller, R. Agüero, H. Karl, in: Broadband Satellite Comunication Systems and the Challenges of Mobility - IFIP TC6 Workshops on Broadband Satellite Communication Systems and Challenges of Mobility, World Computer Congress, August 22-27, 2004, Toulouse, France, 2004, pp. 145--155.
2004 | Conference Paper | LibreCat-ID: 854
Consistency challenges of service discovery in mobile ad hoc networks
C. Frank, H. Karl, in: Proceedings of the 7th International Symposium on Modeling Analysis and Simulation of Wireless and Mobile Systems, MSWiM 2004, Venice, Italy, October 4-6, 2004, 2004, pp. 105--114.
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C. Frank, H. Karl, in: Proceedings of the 7th International Symposium on Modeling Analysis and Simulation of Wireless and Mobile Systems, MSWiM 2004, Venice, Italy, October 4-6, 2004, 2004, pp. 105--114.
2004 | Conference Paper | LibreCat-ID: 855
A Geometric Derivation of the Probability of Finding a Relay in Multi-rate Networks
L. Marie Feeney, D. Hollos, M. Kubisch, S. Mengesha, H. Karl, in: NETWORKING 2004, Networking Technologies, Services, and Protocols; Performance of Computer and Communication Networks; Mobile and Wireless Communication, Third International IFIP-TC6 Networking Conference, Athens, Greece, May 9-14, 2004, Proceedings, 2004, pp. 1312--1317.
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L. Marie Feeney, D. Hollos, M. Kubisch, S. Mengesha, H. Karl, in: NETWORKING 2004, Networking Technologies, Services, and Protocols; Performance of Computer and Communication Networks; Mobile and Wireless Communication, Third International IFIP-TC6 Networking Conference, Athens, Greece, May 9-14, 2004, Proceedings, 2004, pp. 1312--1317.
2004 | Conference Paper | LibreCat-ID: 856
Regionalizing global optimization algorithms to improve the operation of large ad hoc networks
D. Hollos, H. Karl, A. Wolisz, in: 2004 IEEE Wireless Communications and Networking Conference, WCNC 2004, Atlanta, Georgia, USA, 21-25 March 2004, 2004, pp. 819--824.
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D. Hollos, H. Karl, A. Wolisz, in: 2004 IEEE Wireless Communications and Networking Conference, WCNC 2004, Atlanta, Georgia, USA, 21-25 March 2004, 2004, pp. 819--824.
2004 | Conference Paper | LibreCat-ID: 857
Queue-driven cut-through medium access in wireless ad hoc networks
D. Raguin, M. Kubisch, H. Karl, A. Wolisz, in: 2004 IEEE Wireless Communications and Networking Conference , WCNC 2004, Atlanta, Georgia, USA, 21-25 March 2004, 2004, pp. 1909--1914.
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D. Raguin, M. Kubisch, H. Karl, A. Wolisz, in: 2004 IEEE Wireless Communications and Networking Conference , WCNC 2004, Atlanta, Georgia, USA, 21-25 March 2004, 2004, pp. 1909--1914.
2004 | Book Chapter | LibreCat-ID: 858
Data Transmission in Mobile Communication Systems
H. Karl, in: Location-Based Services, 2004, pp. 207--244.
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H. Karl, in: Location-Based Services, 2004, pp. 207--244.
2004 | Conference (Editor) | LibreCat-ID: 859
Wireless Sensor Networks
H. Karl, A. Willig, A. Wolisz, eds., Wireless Sensor Networks, First European Workshop, {EWSN} 2004, Berlin, Germany, January 19-21, 2004, Proceedings, 2004.
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H. Karl, A. Willig, A. Wolisz, eds., Wireless Sensor Networks, First European Workshop, {EWSN} 2004, Berlin, Germany, January 19-21, 2004, Proceedings, 2004.
2004 | Conference Paper | LibreCat-ID: 988
Ambient Networks--Research for Communication Networks Beyond 3G
N. Niebert, H. Flinck, R. Hancock, H. Karl, C. Prehofer, in: 13th IST Mobile and Wireless Communications-Summit 2004, 2004.
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N. Niebert, H. Flinck, R. Hancock, H. Karl, C. Prehofer, in: 13th IST Mobile and Wireless Communications-Summit 2004, 2004.
2004 | Conference Paper | LibreCat-ID: 992
Throughput study for a dynamic OFDM-FDMA system with inband signaling
J. Gross, I. Paoluzzi, H. Karl, A. Wolisz, in: Vehicular Technology Conference, 2004. VTC 2004-Spring. 2004 IEEE 59th, 2004, pp. 1787--1791.
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J. Gross, I. Paoluzzi, H. Karl, A. Wolisz, in: Vehicular Technology Conference, 2004. VTC 2004-Spring. 2004 IEEE 59th, 2004, pp. 1787--1791.
2004 | Journal Article | LibreCat-ID: 993
A hybrid approach for location-based service discovery in vehicular ad hoc networks
N. Klimin, W. Enkelmann, H. Karl, A. Wolisz, Proc. of WIT (2004).
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N. Klimin, W. Enkelmann, H. Karl, A. Wolisz, Proc. of WIT (2004).
2004 | Conference Paper | LibreCat-ID: 997
Distributed allocation of time slots for real-time traffic in a wireless multi-hop network
E. Carlson, H. Karl, A. Wolisz, C. Prehofer, in: Proc. European Wireless, 2004.
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E. Carlson, H. Karl, A. Wolisz, C. Prehofer, in: Proc. European Wireless, 2004.
2004 | Journal Article | LibreCat-ID: 998
Capacity increase of multi-hop cellular wlans exploiting data rate adaptation and frequency recycling
S. Mengesha, H. Karl, A. Wolisz, Proc. of MedHocNet 2004 (2004).
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S. Mengesha, H. Karl, A. Wolisz, Proc. of MedHocNet 2004 (2004).
2004 | Conference Paper | LibreCat-ID: 1002
Distributed maintenance of resource reservation paths in multihop 802.11 networks
E. Carlson, C. Bettstetter, H. Karl, C. Prehofer, A. Wolisz, in: Vehicular Technology Conference, 2004. VTC2004-Fall. 2004 IEEE 60th, 2004, pp. 2994--2998.
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E. Carlson, C. Bettstetter, H. Karl, C. Prehofer, A. Wolisz, in: Vehicular Technology Conference, 2004. VTC2004-Fall. 2004 IEEE 60th, 2004, pp. 2994--2998.
2004 | Conference Paper | LibreCat-ID: 1006
On the effect of inband signaling and realistic channel knowledge on dynamic OFDM-FDMA systems
J. Gross, H. Karl, A. Wolisz, in: European Wireless 2004, 2004.
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J. Gross, H. Karl, A. Wolisz, in: European Wireless 2004, 2004.
2004 | Journal Article | LibreCat-ID: 1017
A MAC protocol for wireless sensor networks with multiple selectable, fixed-orientation antennas
M. Kubisch, H. Karl, A. Wolisz, Frequenz (2004) 92--96.
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M. Kubisch, H. Karl, A. Wolisz, Frequenz (2004) 92--96.
2004 | Conference Paper | LibreCat-ID: 1019
Throughput optimization of dynamic OFDM-FDMA systems with inband signaling
J. Gross, H. Karl, A. Wolisz, in: 2nd International Symposium on Modeling and Optimization in Mobile, Ad Hoc, and Wireless Networks 2004 (WiOpt 2004), 2004.
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J. Gross, H. Karl, A. Wolisz, in: 2nd International Symposium on Modeling and Optimization in Mobile, Ad Hoc, and Wireless Networks 2004 (WiOpt 2004), 2004.