Design of Antennas for Handheld DVB-H ... - Lunds tekniska högskola

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Every section has information in the header about start address for the IP datagram. The address indicates the position for the first byte of the IP datagram in the application table. This application data is followed by the parity bytes in the RS data table that are read out column by column and encapsulated in separate MPE-FEC sections. The FEC frame structure also contains a block interleaving effect in addition to coding. That means that the receiver can put the datagram in right order in the application table and mark it “reliable” for the RS decoder. A flag marks the end of the application data table. If all application data is received correctly none of the MPE-FEC sections are necessary. That is optimal if time slicing is used, because then the receiver can go to sleep [17]. 2.1.5.5 4K mode Figure 2.6. The MPE-FEC frame. DVB-T provides two different modes for different topologies, 2K and 8K mode. DVB-H also disposes of an intermediate 4K mode that has a little of both 2K and 8K modes qualities. The qualities of the different modes can be seen in Table 2.1. It allows twice as long distance between receiver and transmitter in SFNs compared to the 2K mode and it is less susceptible to Doppler frequencies in case of mobile reception compared to the 8K mode. The 4K mode shall make the network planning for DVB-H easier, this does not apply for DVB-T since it does not include the 4K mode [10]. To make transmissions with the 4K mode possible a new symbol interleaver with 4096 OFDM carrier frequencies was specified. In connection with the three network modes a new symbol-interleaving scheme is defined (See figure 2.7). A DVB-H terminal should support all three modes and then needs an 8K symbol interleaver. It is preferred to use the relatively big memory of the 8K symbol interleaver in all three network modes. This symbol interleaver is able to process the amount of one complete 8K OFDM symbol or alternatively two 4K OFDM 14
symbols or four 2K OFDM symbols. This way the memory is used more effectively and it results in an increased interleaving depth in the 2K and 4K modes, which can be expected to improve performance. If the full memory interleaving solution is used it is called in-depth interleaving [15]. Table 2.1. Qualities for the three different modes. Mode OFDM parameter 2K 4K 8K Overall carriers (=FFT size) 2048 4096 8192 Modulated carriers 1705 3409 6817 Useful carriers 1512 3024 6048 OFDM symbol duration (µs) 224 448 896 Guard interval duration (µs) 7, 14, 28, 56 14, 28, 56,112 28, 56,112,224 Carrier spacing (kHz) 4.464 2.232 1.116 Maximum distance of transmitters (km) 17 33 67 Figure 2.7. DVB-H symbol interleaving scheme. 2.1.5.6 Transmission Parameter Signalling - TPS So called TPS data is provided in DVB-H to inform the receiver about the modulation and coding scheme and wheter DVB-H-specific features are used and if so, which ones. The TPS is transmitted in parallel on 17 TPS carriers for the 2k mode, 34 carriers for 4k mode and on 68 carriers for 8k mode. The TPS is defined over 68 OFDM symbols, referred to as one OFDM frame. Each TPS block contains 68 bits, defined as table 2.2. 15
Page 1 and 2: Design of Antennas for Handheld DVB
Page 3 and 4: Acknowledgements This master thesis
Page 5 and 6: 4 DESIGN AND TESTING OF ANTENNA SOL
Page 7 and 8: Figure 5.2. Reference dipole antenn
Page 9 and 10: 1 Introduction The passed decade th
Page 11 and 12: 2 Background This chapter provides
Page 13 and 14: is simultaneously modulated into 10
Page 15 and 16: 2.1.3 Reed-Solomon Codes 2.1.4 DVB-
Page 17 and 18: 2.1.5 DVB-H DVB-H is the latest dev
Page 19 and 20: 2.1.5.2 Time slicing A large proble
Page 21: figure 2.5). All three elements tog
Page 25 and 26: 2.2 Competing standards The DVB-H s
Page 27 and 28: 2.3 Antenna theory This section des
Page 29 and 30: Figure 2.9. Impedance bandwidth def
Page 31 and 32: unloaded quality factor (Q0) and th
Page 33 and 34: losses should be avoided in handhel
Page 35 and 36: 3.3 Loop Figure 3.1. Yagi-Uda anten
Page 37 and 38: PIFA Figure 3.2. Four different con
Page 39 and 40: The size of the antenna is another
Page 41 and 42: 4.4 PIFA To verify the balun a resi
Page 43 and 44: 4.5 Folded-Patch With the PIFA-ante
Page 45 and 46: Figure 4.9a. Folded-patch 2, front
Page 47 and 48: Figure 4.11. Loop antenna schematic
Page 49 and 50: Figure 4.15. Wire loop antenna retu
Page 51 and 52: using an H-field antenna together w
Page 53 and 54: antenna. The dimension of the anten
Page 55 and 56: The result of the return loss measu
Page 57 and 58: Figure 4.24. Return loss graph for
Page 59 and 60: The result of the measurement of th
Page 61 and 62: Figure 4.31. Return loss graph for
Page 63 and 64: frequency band, the first from 470
Page 65 and 66: Figure 5.6. Radiation pattern for R
Page 67 and 68: 5.1.3 Measurement result In this ch
Page 69 and 70: Figure 5.10. Radiation pattern for
Page 71 and 72: Figure 5.12. Radiation pattern for
Page 73 and 74:
Table 5.4. Switched monopole 1, gai
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Power gain / dB 2 0 -2 -4 -6 -8 -10
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Figure 5.22. Radiation pattern for
Page 79 and 80:
was received in all five channels.
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6.3 Control signal 6.4 Cost The swi
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not be possible, there will always
Page 85 and 86:
There are many advantages with tuna
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8 References [1] Schiller, Jochen -
Page 89:
[29] Gardiol, Fred - Microstrip cir
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Design of Antennas for Handheld DVB-H ... - Lunds tekniska högskola

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