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Digital TV by Cable
Published in Lars-Ingemar Lundström, Understanding Digital Television, 2012
Below 300 MHz, not that many channels can be used for distribution. The bandwidth of the channels are 7 MHz wide and in the lowest frequency band, band I (47–64 MHz), there are only three channels: channel 2, 3 and 4. Channel 1 does not even exist. The next frequency band, band II (87–108 MHz) is used for FM radio. The third band, band III, (174–230 MHz) covers the channels 5 through 12. Channel numbers mentioned here applies to continental Europe.
Vibrational spectroscopy of free di-manganese oxide cluster complexes with di-hydrogen
Published in Molecular Physics, 2023
Sandra M. Lang, Thorsten M. Bernhardt, Joost M. Bakker, Bokwon Yoon, Uzi Landman
Thus, we conclude that the IR-MPD spectra of Mn2O4H2+ and Mn2O4D2+ with the observed isotope shift (bands α and β) are best described by isomer A. However, this isomer cannot account for the experimental bands i and ii. These bands appear upon hydrogen adsorption (cf. Figure 3) but do not show any isotope shift (cf. Figure 2), that is, they cannot involve motions that are dominated by the hydrogen atoms. Although band ii might potentially be explained by features of isomer B and B’ (but these isomers are unlikely to be present in considerable amount), the triad i cannot be explained by any of the studied isomers. Since, however, this triad bears some similarity to band II, it is reasonable to assign these bands to a combination of band II with the low frequency band IV. Both bands are also present in the spectrum of the bare Mn2O4+ cluster and are thus independent of H2. The observation of these combination bands in the spectrum of the hydrogen complexes but not in the spectrum of the bare cluster might be attributed to the presence of a rather weakly bound H2 (D2) molecule (binding energy of 0.42 eV) which makes it a good leaving group, allowing less intense features to become visible. Finally, band ii might also arise from a combination of band III with another low frequency mode.
High-resolution spectroscopic study of the H2O–CO2 van der Waals complex in the 2OH overtone range
Published in Molecular Physics, 2020
C. Lauzin, A. C. Imbreckx, T. Foldes, T. Vanfleteren, N. Moazzen-Ahmadi, M. Herman
226 lines were assigned for band II (7238 cm) and 259 lines for the band I (7247 cm). All assignments for lines with J<6 and were verified using combination differences from the work of Columberg et al. [5]. The rotational constants are presented in Table 2. Although not all observed lines are accounted for in the analysis, the agreement between simulated and observed spectra is satisfactory for band I. Severe perturbations were observed for band II, in particular, for the 0–1 subband which presents an irregular pattern in terms of intensity namely for the to , as illustrated by asteriks in Figure 3. One should, however notice that these local perturbations are consistent for P/Q/R lines with the same upper rotational level. Their origin remain unassigned.
Reconfigurable radio receiver with fractional sample rate converter and multi-rate ADC based on LO-derived sampling clock
Published in International Journal of Electronics, 2018
Sungkyung Park, Chester Sungchung Park
The sampling clock generator which functions as a frequency divider and buffer is needed between the LO and the clock input to the delta-sigma ADC. In the first place, a multiple of LO frequency ranges are considered for UTRA/FDD cellular bands: ×2 LO for band I (2110–2170 MHz) corresponds to 4220–4340 MHz, ×2 LO for band II corresponds to 3860–3980 MHz, ×2 LO for band III corresponds to 3610–3760 MHz, ×2 LO for band IV corresponds to 4220–4310 MHz, ×4 LO for band V (869–894 MHz) corresponds to 3476–3576 MHz, ×4 LO for band VI corresponds to 3500–3540 MHz, ×4 LO for band VIII corresponds to 3700–3840 MHz, ×2 LO for band IX corresponds to 3690–3760 MHz. For each of these bands, appropriate choice between divide-by-12 or divide-by-14 logic for the sampling clock generator determines the frequency range of the ADC clock input. For band I, for example, divide-by-14 logic makes the frequency range of the ADC clock input 301–310 MHz and for band II divide-by-12 logic makes the frequency range 322–332 MHz. The common frequency range covering all of these bands is 290–332 MHz. Similarly, ×2 or ×4 LO for band VII, DCS 1800 band, PCS 1900 band, E-GSM 900 band and GSM 850 band with appropriate choice between divide-by-12 or divide-by-16 logic determines the frequency range of the ADC clock input. The common frequency range covering all the five bands is 289–337 MHz.