{"id":692523,"date":"2024-11-06T05:29:48","date_gmt":"2024-11-06T05:29:48","guid":{"rendered":"https:\/\/pdfstandards.shop\/product\/uncategorized\/tia-eia-is-641-a1998\/"},"modified":"2024-11-06T05:29:48","modified_gmt":"2024-11-06T05:29:48","slug":"tia-eia-is-641-a1998","status":"publish","type":"product","link":"https:\/\/pdfstandards.shop\/product\/publishers\/tia\/tia-eia-is-641-a1998\/","title":{"rendered":"TIA\/EIA\/IS-641-A:1998"},"content":{"rendered":"

Preface<\/strong><\/p>\n

This document gives a description of the Nokia\/JSH speech and
\nchannel codec for the TIA IS-641 Enhanced Full Rate Codec. The
\ncodec consists of a 7.4 kbit\/s ACELP speech codec and a 5.6 kbit\/s
\nchannel codec (Forward Error Correction).<\/p>\n

Section 1 gives a general description of the speech coder and
\nsections 2 and 3 give more detailed descriptions of the speech
\nencoder and the speech decoder, respectively. Section 4 gives a
\ndetailed description of the channel encoder. The channel decoder in
\nsection 5 is not considered as part of this standard. The bad frame
\nmasking described in section 5. 1 is provided as an example
\nsolution; other solutions are allowed. Section 6 gives a detailed
\ndescription of the different aspects of Discontinuous Transmission
\n(DTX). The bad frame masking described in section 6.4.4 is provided
\nas an example solution; other solutions are allowed.<\/p>\n

This standard consists of this document and a soft copy
\ndistribution comprising four diskettes. These contain a bit-exact
\ndescription in the form of a fixed point ANSI C code and a number
\nof test sequences. The C code defines the speech codec and the
\nchannel encoder with a set of fixed point basic operators. The test
\nvectors are described in Annex A. A detailed description of the
\ncontents and formats of the soft copy distribution is given in
\nAnnex B. The details of the instability protection for the speech
\ncodec are given in Annex C. Annex D describes a reference design of
\na voice activity detector (VAD) which may be used to implement the
\nDTX mode of the speech encoder in the mobile station (MS).<\/p>\n

MS implementations shall be bit-exact. Bit-exact implementations
\nare subject to the test vectors specified in this standard. Base
\nstation implementations are not required to be bit-exact. However,
\nnon bit-exact validation is subject to the minimum performance
\nrequirements for the Enhanced Full Rate codec contained in
\nIS-686.<\/p>\n

In the case of discrepancy between the high level and the
\nbit-exact descriptions, the description in the bit-exact C program
\nwill prevail.<\/p>\n","protected":false},"excerpt":{"rendered":"

TDMA – Cellular PCS – Radio Interface Enhanced Full-Rate Voice Codec<\/b><\/p>\n\n\n\n\n
Published By<\/td>\nPublication Date<\/td>\nNumber of Pages<\/td>\n<\/tr>\n
TIA<\/b><\/a><\/td>\n1998<\/td>\nNA<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n","protected":false},"featured_media":0,"template":"","meta":{"rank_math_lock_modified_date":false,"ep_exclude_from_search":false},"product_cat":[2646],"product_tag":[],"class_list":{"0":"post-692523","1":"product","2":"type-product","3":"status-publish","5":"product_cat-tia","7":"first","8":"instock","9":"sold-individually","10":"shipping-taxable","11":"purchasable","12":"product-type-simple"},"_links":{"self":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product\/692523","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/types\/product"}],"wp:attachment":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/media?parent=692523"}],"wp:term":[{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_cat?post=692523"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_tag?post=692523"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}