TIA-EIA-IS-718-1998.pdf
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1、f STD-EIA TIA/IS-7LB-ENGL 1778 W 323i-lb00 ObU5b5i ObU TIAIEIA INTERIM STANDARD Minimum Performance Specification for the Enhanced Variable Rate Codec, Speech Service Option 3 for Spread Spectrum Digital Systems TIAIEIAIIS-718 TELECOMMUNICATIONS INDUSTRY ASSOCIATION Electronic Industries Alliance Co
2、pyright Telecommunications Industry Association Provided by IHS under license with EIALicensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/29/2007 20:54:37 MDTNo reproduction or networking permitted without license from IHS -,-,- STD-EIA TIA/IS-718-ENGL 1998 m 3234bOO Ob05b55 TT7
3、m NOTICE TIAEL4 Engineering Standards and Publications are designed to serve the public interest through eliminating misunderstandings between manufacturers and purchasers , facilitating interchangeability and improvement of products, and assisting the purchaser in selecting and obtaining with minim
4、um delay the proper product for his particular need. Existence of such Standards and Publications shall not in any respect preclude any member or nonmember of TIAEIA from manufacturing or selling products not conforming to such Standards and Publications, nor shall the existence of such Standards an
5、d Publications preclude their voluntary use by those other t h a n TIALEIA members, whether the standard is to be used either domestically or internationally. Standards and Publications are adopted by TIA/EIA in accordance with the American National Standards Institute (ANSI) patent policy. By such
6、action, TA/EIA does not assume any liability to any patent owner, nor does it assume any obligation whatever to parties adopting the Standard or Publication. TIAEIAINTERIM STANDARDS TIA/EA Interim Standards contain information deemed to be of technical value to the industry, and are published at the
7、 request of the originating Committee without necessarily following the rigorous public review and resolution of comments which is a procedural part of the development of a TIAEIA Standard. TIA/EA Inerim Standards should be reviewed on an annual basis by the formulating Committee and a decision made
8、 on whether t o proceed to develop a TIA/EIA Standard on this subject. TIA/EiA Interim Siandards must be cancelled by the Committee and removed from the “MEIA Standards Catalog before the end of their third year of existence. Publication of this TIA/EIA Interim Standard for t r i a l use and comment
9、 has been approved by the Telecommunications Industry Association. Distribution of this TIALEIA Interim Standard for comment shaii not continue beyond 36 months from the date of publication. It is expected that following this 36 month period, diis TIA/EIA Interim Siandard, revised as necessary, will
10、 be submitted to the American National Standards Institute for approval as an American National Standard. Suggestions for revision should be directed to: E r i c Schimmel, Standards otherwise the test codec fails - 6 2.2 Subjective Performance Testing 7 This section outlines the subjective testing m
11、ethodology of the subjective performance test. 8 The purpose of this testing is to evaluate the quality of the test codec under a variety of 9 conditions which may occur in the CDMA system. To accomplish this, two listening I O experiments have been designed to test speech codec quality under a vari
12、ety of conditions. II These conditions include channel impairments, codec tandem, audio background noise and 12 different input levels. In addition, half-rate maximum operation of the codec will be 13 examined. 14 2.2.1 Defmition I S 16 17 18 i The codec subjective test is intended to validate the i
13、mplementation of the speech codec being tested using the master codec defmed in 3.4 as a reference. The subjective test is based on the Absolute Category Rating or Mean Opinion Score (MOS) test as described in ITU Blue Book Vol. V, Supplement 14, Annex All. 19 - . 20 21 22 23 24 25 26 27 28 2.2.2 Me
14、thod of Measurement The subjective test involves a listening-only assessment of the quality of the codec being tested, using the master codec as a reference. Subjects from the general population of telephone users will rate the various conditions of the test. Material supplied with this standard for
15、 use with this test includes source speech, impaired packet files from the master codec encoder, and source speech processed by Vanous Modulated Noise Reference Unit (MNRU) conditions and other references. The basic Absolute Categov Rating test procedure involves rating ail conditions using a five-p
16、oint scale describing the opinion of the test condition, This procedure is fully described in ITU Blue Book Vol. V, Supplement 14, Annex A 1 i. 29 2.2.3 Test Conditions 30 The two listening experiments are similar in design. Each experiment will test the same 31 number of codecs, and the number of t
17、est conditions for each experiment is five. There will 32 be one condition typifying CDMA channels (3% FER), a clear channel condition and a clear 33 channel tandem condition. A i l tandem conditions shall be asynchronous, where 34 asynchronous implies the introduction of a partial frame offset betw
18、een encoding 35 operations. A nominal input level of -22 dB shall be used for these conditions. Additional 36 test conditions include background noise and audio input level variation. - - 37 For reference, y-law, 4 MNRU conditions (5, 15, 20 and 25 dBQ values) and G.728 (LD- 38 CELP) will be include
19、d in each experiment. Also, IS-96-A is included for aii conditions as 39 an additional reference. 2-2 Copyright Telecommunications Industry Association Provided by IHS under license with EIALicensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/29/2007 20:54:37 MDTNo reproduction or
20、 networking permitted without license from IHS -,-,- TIA/EIA/IS-718 i 2.2.3.1 Subjective Experiment I z Listening experiment I contains the five test conditions shown in Table 2.2.3.1-1. 3 4 Table 2 . 2 . 3 . 1 - 1 . Listening Experiment I (2) High Audio Input Level -12 dB (3) Low Audio Input Level
21、-32 dB (4) 3% FER (forward and reverse) 2-3 Copyright Telecommunications Industry Association Provided by IHS under license with EIALicensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/29/2007 20:54:37 MDTNo reproduction or networking permitted without license from IHS -,-,- 1 2 T
22、- 3 4 - - 5 6 7 6 9 10 i1 12 13 14 Condition Type of test Number of talkers Background noise Audio Input level Filter characteristics Reference conditions Test conditions Number of codecs Encoding stages TIA/EIA/IS-7 18 Description MOS 4 males, 4 females ambient and specified test conditions -22 dB
23、fiat voice p-law source, 5, 15, 20, 25 dBQ , G.728 (1) Clean (2) Car Noise (IRS) at 15 dB S / N (3) Street Noise (fiat) at 12 d E 3 S/N (4) Office Babble (flat) at 20 dB S/N (5) Tandem (5) M/M, T/M, M/T, T/T, IS-96-A single and tandem 2.2.3.2 Subjective Experiment II Listening experiment II contains
24、 the five test conditions shown in Table 2.2.3.2-1. Table 2.2.3.2-1. Listening Experiment II . . 2.2.3.3 Numerologsr for Listening Experiments Table 2.2.3.3-1 describes the numerology that is used for each of the two listening experiments. The frst column is a variable name given to each of the para
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- TIA EIA IS 718 1998
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