band spectrum


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Band spectrum

A spectrum consisting of groups or bands of closely spaced lines. Band spectra are characteristic of molecular gases or chemical compounds. When the light emitted or absorbed by molecules is viewed through a spectroscope with small dispersion, the spectrum appears to consist of very wide asymmetrical lines called bands. These bands usually have a maximum intensity near one edge, called a band head, and a gradually decreasing intensity on the other side. In some band systems the intensity shading is toward shorter waves, in others toward longer waves. Each band system consists of a series of nearly equally spaced bands called progressions; corresponding bands of different progressions form groups called sequences.

When spectroscopes with adequate dispersion and resolving power are used, it is seen that most of the bands obtained from gaseous molecules actually consist of a very large number of lines whose spacing and relative intensities, if unresolved, explain the appearance of bands of continua. For the quantum-mechanical explanations of the details of band spectra See Molecular structure and spectra.

band spectrum

A spectrum consisting of one or more bands of emitted or absorbed radiation. The bands consist of numbers of closely spaced lines and result from transitions between energy levels in molecules, allowing different levels of vibration or rotation.

band spectrum

[′band ‚spek·trəm]
(spectroscopy)
A spectrum consisting of groups or bands of closely spaced lines in emission or absorption, characteristic of molecular gases and chemical compounds. Also known as band.
References in periodicals archive ?
According to a Money Control report, the DoT will soon formally reject the operators' demand for licence extension along with 900MHz band spectrum auction.
For example, the 900 MHz band spectrum in Europe, originally dedicated to GSM use, is now being used to roll out UMTS networks.
In recent years, technological advances have increased the ability to harness millimeter wave (mmW) technology for fixed and mobile wireless communications in high band spectrum, while demand for connected products and services continues to grow.
Bharti Airtel and Vodafone will have to bid aggressively to retain the prime 900 MHz band spectrum in the lucrative Delhi, Mumbai and Kolkata circles as their licences expire in November and Mukesh Ambani- led Reliance Jio ( RJI) will also compete against them.
2 ( ANI ): The Telecom Regulatory Authority of India (TRAI) has released a consultation paper on reserve price for auction of 800 MHz Band spectrum.
He added that the 700 band spectrum is currently being used by security services, and that the ministry is working to obtain it.
The deal, worth Rs 5,000 crore, will allow RCOM to acquire SSTL's 800 / 850 MHz band spectrum, ideally suited for 4G LTE services.
The Telecom Commission, the highest decisionmaking body of DoT, last week decided to overrule Trai as it was of the view that it could earn revenue through the sale of the 800 MHz band spectrum and reduce the fiscal deficit.
According to reports 800MHz band spectrum auction is slated to start two days after the government announces the winners of 1,800 MHz band auction.
Around 15 MHz of the 900 MHz band spectrum has to be refarmed in Delhi and Mumbai and 12.
The PMO clarified that no decision has been taken by the Government to allocate space segment using S Band Spectrum to ANTRIX Corporation or Devas Multimedia.
T-Mobile has doubled its LTE coverage since 2015, and its newly acquired premium low band spectrum will broaden its LTE footprint even further and lay the foundation for the countrys first nationwide 5G network.