Sökning: "Wireless Channel"

Visar resultat 1 - 5 av 377 avhandlingar innehållade orden Wireless Channel.

1. 1. Broadband Wireless OFDM Systems

   Författare :Maxime Flament; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; channel model; 4th Generation Wireless 4GW ; shadowing; MMIC; WLAN; scenarios; mobile data; OFDM; turbo codes; propagation; license-exempt bands; coding; 60 GHz channel; broadband wireless; interference; Virtual Cellular Network VCN ; front-end;

   Sammanfattning : While the readiness of the telecommunication market and the users' need for broadband mobile data are not currently noticeable, a set of presented megatrends and scenarios suggest that broadband mobile data access will develop quickly in the next ten years. Identification of the potential frequency bands offering cheap and trouble-free wireless infrastructure is therefore an important step towards the definition of new air interfaces. LÄS MER

3. 2. Channel Related Optimization of Wireless Communication Systems

   Författare :Fredrik Tufvesson; Institutionen för elektro- och informationsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; time division duplex; multicarrier; Radio communication; orthogonal frequency division multiplex; channel estimation; pilot symbol assisted modulation; sub-channel spacing; sub-channel bandwidth; interchannel interference; cyclic prefix; intersymbol interference; Rayleigh fading; precoding; pre-compensation;

   Sammanfattning : This thesis deals with different optimization problems in the design of wireless communication systems. It is mainly directed to the design of systems based on multicarrier techniques and orthogonal frequency division multiplex, OFDM, but some of the problems apply to single carrier systems as well. LÄS MER

4. 3. Baseband Processing for 5G and Beyond: Algorithms, VLSI Architectures, and Co-design

   Författare :Mojtaba Mahdavi; Institutionen för elektro- och informationsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; VLSI Implementation; Hardware architectures; ASIC implementation; FPGA implementation; CMOS Technology; Baseband Processing; Massive MIMO; 5G New Radio; Beyond 5G; Co-Design; FFT processor; OFDM modulation; wireless communications; Massive MIMO Detection; Angular domain processing; Zero forcing; Systolic array; Non-linear detector; Channel Sparsity; Channel compression; Linear detector; Channel coding; Spatial coupling; Turbo-like codes; Spatially coupled serially concatenated codes; Threshold analysis; Decoder architecture; BCJR algorithm; MAP algorithm; Coupling memory; Window decoding; Complexity analysis; Performance Evaluation; Throughput; Decoding Latency; Silicon area; Design tradeoffs; Interleaver architecture; Memory requirements; Matrix multiplication; Channel state information CSI ; Cholesky decomposition; Tanner graph; Trellis codes; Convolutional encoder; Code design; Puncturing; Reordering circuit; wireless communication system; digital electronic;

   Sammanfattning : In recent years the number of connected devices and the demand for high data-rates have been significantly increased. This enormous growth is more pronounced by the introduction of the Internet of things (IoT) in which several devices are interconnected to exchange data for various applications like smart homes and smart cities. LÄS MER

5. 4. Design of Wireless Communication Systems -- Issues on Synchronization, Channel Estimation and Multi-Carrier Systems

   Författare :Fredrik Tufvesson; Institutionen för elektro- och informationsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; pre-compensation; pilot pattern; Elektronik; orthogonal frequency division multiplex; Wireless; synchronization; detection; preambles; channel estimation; Electronics; superimposed pilot sequences; sub-channel bandwidth; precoding;

   Sammanfattning : This thesis deals with certain aspects in the design of wireless communications systems. It is focused on problems related to the mobile or wireless channel: synchronization, channel estimation and design of wireless orthogonal frequency division multiplex (OFDM) systems. LÄS MER

7. 5. Channel Shortening in Wireless Communication

   Författare :Sha Hu; Kommunikationsteknologi; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Channel shortening CS ; multi-input multi-output MIMO ; intersymbol interference ISI ; achievable information rate AIR ; partial marginalization PM ; dirty paper coding DPC ; large intelligent surface LIS ; Cramér-Rao lower bound CRLB ;

   Sammanfattning : The concept of Channel Shortening (CS) is a well-known technique that has a rich history over 40 years. CS transfers linear vector channels such as multi-input multi-output (MIMO) and intersymbol interference (ISI) channels into ``shortened'' versions, for the purpose of reducing demodulation-complexity and improving data-transmission performance. LÄS MER