band spectrum


Also found in: Dictionary, Wikipedia.

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 ?
can purchase EZ LTE directly via Lemko's website and deploy LTE based on the FCC Citizen Band Spectrum rules.
He added that the 700 band spectrum is currently being used by security services, and that the ministry is working to obtain it.
Around 15 MHz of the 900 MHz band spectrum has to be refarmed in Delhi and Mumbai and 12.
THE Supreme Court on Friday gave a go- ahead to Devas Multimedia Pvt Ltd for initiation of arbitration proceedings outside India over cancellation of S- band spectrum granted to it by Antrix Corp Ltd, which is the commercial wing of the Indian Space Research Organisation ( ISRO).
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.
On the other hand, 70 megahertz of S- band spectrum was earmarked for Devas.
The Un-carrier today confirmed its Extended Range LTE , or 700 MHz low band spectrum, which now carries T-Mobile s LTE signals both farther and deeper indoors, is now live throughout the greater Indianapolis area.
PRIME Minister Manmohan Singh on Thursday dragged the NDA government into the controversy over S- band spectrum in the Antrix- Devas deal.
The document also reviews the diversity of band spectrum for WiMAX-certified Metro Area Network (MAN) deployment, which is creating new demand for base stations and subscriber stations with varying RF requirements.
Post-transaction, T-Mobile will have low band spectrum in 9 of the top 10 and 21 of the top 30 U.
The Association also pointed out that 90 percent of the world's mobile operators that have been awarded licences to deploy 3G services, have been granted IMT2000 core band spectrum on a technology neutral basis.
For example, the 900 MHz band spectrum in Europe, originally dedicated to GSM use, is now being used to roll out UMTS networks.