China
Africa
Explore chapters and articles related to this topic
Digital Audio Broadcasting
Published in Jerry D. Gibson, Mobile Communications Handbook, 2017
Digital Audio Broadcasting (DAB) is more spectrally efficient than analog FM. In addition to the improved quality requirements, this spectral-efficiency advantage of digital over analog was one of the driving forces behind the development of DAB. The increased spectral efficiency of digital transmission (with respect to analog FM) effectively means that a larger number of radio programs can be broadcasted over a given bandwidth. Another key advantage was the flexibility in transmission offered by the digital technology. Thus, auxiliary services (data services) can be obtained in addition to high-quality audio. Examples of such services are traffic information, weather information, stock quotations, image and even video services, and so on.
Squeezing through the pipe: digital compression
Published in Jonathan Higgins, Satellite Newsgathering, 2012
The ISO/IEC MPEG established in 1988 considered digital compression standards for audio as well as video material. Meanwhile, under the auspices of a technical body called Eureka – an international consortium of broadcasters, network operators, consumer electronic industries and research institutes – the digital audio broadcasting (DAB) standard was being developed to replace conventional broadcast radio technology (analog AM and FM). DAB is the most fundamental advance in radio technology since the introduction of FM stereo radio, as it gives listeners interference-free reception and high-quality sound, and the potential for enhanced text and information services.
Joint CFO and channel estimation using pilot aided interpolation for high performance MIMO-OFDM
Published in International Journal of Electronics, 2023
S. Chitra, S. Ramesh, Ramya Vijay, G. Jegan, T. Samraj Lawrence
Orthogonal frequency division multiplexing (OFDM) has gained more attention in fourth and fifth generation (4 G and 5 G) wireless standards due to its high throughput, spectral efficiency, robustness to multipath fading and simple implementation with inverse fast Fourier transform (IFFT) and FFT algorithms. The principle of OFDM is dividing the total bandwidth into a number of orthogonal subcarriers, each with a narrow bandwidth. Since the subcarrier bandwidth is less than the coherence bandwidth of the channel, flat fading is possible in each subcarrier. As the frequency selective fading is converted to flat fading, OFDM system has reduced intersymbol interference (ISI), which simplifies the equaliser’s design. OFDM finds applications in digital video broadcasting, digital audio broadcasting, asymmetric digital subscriber line (ADSL) and IEEE 802.11 wireless LAN standards. The performance of 4 G and 5 G wireless services over multipath frequency selective fading channels can be improved by combining MIMO and OFDM algorithms.
An efficient SLM technique based on chaotic biogeography-based optimization algorithm for PAPR reduction in GFDM waveform
Published in Automatika, 2023
S. Selvin Pradeep Kumar, C. Agees Kumar, R. Jemila Rose
As an air interface technique, several wireless protocols include Orthogonal Frequency Division Multiplexing (OFDM) [3]. DAB (digital audio broadcasting), DVBT (digital video broadcasting for terrestrial television), WLAN (802.11family), and 4G cellular technologies are all examples (LTE-A). OFDM has several advantages, including low complexity equalization, which makes it immune to inter-symbolic interference (ISI). This is accomplished through the use of a Cyclic Prefix (CP) and Frequency Domain Equalization (FDE). The efficient use of IFFT/FFT processing reduces the Waveform processing. Seyye Hadi et al. [4] proposed the greedy deterministic algorithms based on the OFDM system. In this technique, they optimize the value with the help of pilot. The pilot are references signal to use in transmit and receive side.
An efficient and improved PTS algorithm for PAPR reduction in OFDM system
Published in International Journal of Electronics, 2022
Prabal Gupta, H. Pal Thethi, Ajay Tomer
This paper depicts practice for reduction of PAPR concern after utilizing well-organized PTS algorithm with CPSM for several N like 64,128,256 and 512 with 32-PSK,16-PSK and 8-PSK under L = 4,8 and also U = 2,8. PTS algorithm undergoes difficulty in the creation of phase sequences. For this reason, this particular issue needs advanced solution. The performance explorations disclose that PROPOSED-PTS-ALGO-PH-2 and PROPOSED-PTS-ALGO-PH-8 are better in PAPR reduction as compared with Original OFDM system because they utilize the CPSM. It has been observed that creation of the several phase sequences are very systematic and easy. Moreover, the system performance of PROPOSED-PTS-ALGO-PH-2 is further enhanced by PROPOSED-PTS-ALGO-PH-8 because it uses larger number of phase sequences. This has already been justified with excellent simulation results. It can be seen from Figure 2 to Figure 27 that the PROPOSED-PTS-ALGO-PH-8 has superior PAPR reduction than PROPOSED-PTS-ALGO-PH-2, numerous existing techniques and ORIGINAL-OFDM. Moreover, the PROPOSED-PTS-ALGO-PH-8 can meritoriously work with numerous amount of subcarriers, modulation methods and also with BCH code (7,4). Therefore, this proposed algorithm is eligible to act as a strong and more suitable algorithm for many applications like LTE, WLAN, digital video broadcasting (DVB), digital audio broadcasting (DAB), IEEE 802.16d.