Modulation for Digital Radio Broadcasting Using Amplitude Autocorrelation of Pseudo Random Noise Codes to Carry Information

The frequency bands used in mobile communications are allocated according to the type of application. With the need for more channels, the frequency spectrum has become a scarce natural resource. This study shows the results of a proposed modulation using a variation of the autocorrelation of pseudo-random codes to carry information. The work also presents the generation of multiple orthogonal axes to increase the bit rate thus improving the channel efficiency.

Digital Radio Broadcasting for Community Radios Using Pseudo-random Codes

This paper aims to present a digital radio broadcasting system that explores the advantages of pseudo-random codes. In this context, a transmitter and its dual receiver are able to reuse frequency spectrum bands without interfering on other existing communication systems. It is proposed a communication system that allows radio broadcasting with the following characteristics: lower transmission power, new communication channels and digital signal processing techinques to add positioning services in two dimensions.

Factors Influencing Listening Comprehension of English Radio News Broadcasts

Several factors influence listening comprehension of English radio news broadcasts. The study adopted a questionnaire to investigate students' recognition of these factors. On the basis of this analysis, students put emphasis on vocabulary and background knowledge and they were aware of the approaches to better listening comprehension and making some practical preparations before doing the listening tasks. However some differences exist between the effective listeners and less-effective listeners,specially regarding to speech rate and out-of-class relevant practice.

USING RADIO NEWS BROADCASTS AS LISTENING MATERIAL

INTRODUCTION As English teachers, we have devoted a lot of time to the teaching of listening comprehension using radio broadcasts. We began by using VOA news in special English with freshmen and a mixture of news in special English and standard news broadcasts with sophomores. Later BBC news was used. We accumulated a considerable amount of experience and did some research into the design of listening comprehension exercises. This article discusses how listening ability may be improved by using such broadcasts.

Design and analysis of flexible colorless remote node using RSOA-assisted Michelson interferometer

A scheme of flexible colorless remote note with reflective semiconductor optical amplifier （RSOA） assisted Michelson interferometer is proposed. This is capable of generating an optical carrier suppressed signal at a specific radio frequency to suppress the penalty brought about by Rayleigh backscattering and reflection in a full-duplex single fiber transmission network. Simulations are conducted, and the validation of the proposal is discussed by observing the penalty eye opening factor. The results are useful for designing cost-effective multi-wavelength passive optical network （PON） or radio-over-fiber （RoF） systems.

Gigabit-converged wired and wireless networks for simultaneous multi-services transmission

A novel architecture of converged radio-over-fiber （RoF） and wavelength division multiplexed passive optical network （WDM-PON） system, namely RoF-WDM-PON, is demonstrated. 20-GHz 1-Gb/s radio frequency （RF） signals and 1-Gb/s baseband （BB） signals are simultaneously generated and transmitted using optical carrier suppression （OCS） modulation techniques. The proposed scheme is compatible with the conventional RoF and PON system. 25-km single-mode fiber （SMF） transmission is successfully achieved.