1、TIA-968-B ErrataErrata forTIA-968-BTelecommunicationsTelephone Terminal EquipmentTechnical Requirements for Connection ofTerminal Equipment to the Telephone Network12 March 2010Formulated under the cognizance of TIA Technical Regulatory Requirements Subcommittee TR-41.9With the approval of TIA Engin
2、eering Committee TR-41User Premises Telecommunications RequirementsTIA-968-B ErrataThis page was intentionally left blank.TIA-968-B ErrataiErrata for TIA-968-BRationale:During the balloting process for TIA-968-B, a comment was received concerning thewording associated with the equation in subclause
3、5.3.4.1.3 being run together and difficultto read. The comment provided a more legible version of the equation (no technicalchanges). Unfortunately, this corrected version was inserted into the document in place ofthe equation in subclause 5.3.4.1.2 instead of the one in subclause 5.3.4.1.3. In this
4、 errata, the incorrectly replaced equation in subclause 5.3.4.1.2 is restored to itsoriginal version, and the equation with run-together text in subclause 5.3.4.1.3 is replacedwith a more legible version of that equation. Replace:Replace page 123 in TIA-968-B with the attached page 123 showing the c
5、orrect equation insubclause 5.3.4.1.2.Replace page 125 in TIA-968-B with the attached page 125 showing a more legible versionof the equation in subclause 5.3.4.1.3.Note: Table 38 on the intervening page 124 in TIA-968-B is correct No changes to table 38 arenecessary. If you insert the errata pages i
6、nto your copy of TIA-968-B, ensure that table 38is not forgotten or lost. TIA-968-B ErrataThis page was intentionally left blank.TIA-968-B Errata1235.3.4 SHDSL, ESHDSL: 5.3.4.1 SHDSL, ESHDSL signal power limitations: 5.3.4.1.1 Total power for SHDSL and extended SHDSL (ESDSL) shall not exceed +14dBm
7、into 135 ohms.5.3.4.1.2 The power spectral density (PSD) of the signal transmitted by SHDSL shall notexceed the following PSD mask (SHDSLM(f):The in-band PSD for 0 f 1.5 MHz shall be measured with a 10 kHz resolutionbandwidth (RBW).NOTE Large PSD variations over narrow frequency intervals (for examp
8、lenear the junction of the main lobe with the noise floor) might require a smallerresolution bandwidth (RBW) to be used. A good rule of thumb is to chooseRBW such that there is no more than 1 dB change in the signal PSD across theRBW.+=MHzffffffffffffKfSHDSLfetdBMaskedOffsdbsymsymsymSHDSLM1.1,105683
9、.0,1011sin1135)(int5.14int10)(12322where MaskedOffsetdB(f) is defined as:+=dBdBdBdBffffffffetdBMaskedOffs3333,1,4.01)(fintis the frequency where the two functions governing SHDSLM(f) intersect in therange 0 to fsym. KSHDSL, fsym, f3dB, and the line bit rate LBR are defined in table 38. At frequencie
10、s above 1.1 MHz, the conformance criteria of T1.417-2003 clause 6.1shall apply with PT(f) = -110 dBm/Hz and PM(f) = -90 dBm/Hz.TIA-968-B ErrataThis page was intentionally left blank.TIA-968-B Errata1255.3.4.1.3 The power spectral density (PSD) of the signal transmitted by extended SHDSL(ESHDSL) shal
11、l meet the following requirements:For symmetric PSDs using 16-TCPAM payload data rates greater than or equalto 2320 Kbit/s, and for symmetric PSDs using 32-TCPAM payload data ratesgreater than or equal to 768 Kbit/s, the measured transmit PSD of each STU-Rshall not exceed the PSD masks specified in
12、this subclause (PSDMASKSHDSL(f).The in-band PSD for 0 f 2.0 MHz shall be measured with a 10 kHz resolutionbandwidth.NOTE Large PSD variations over narrow frequency intervals (for examplenear the junction of the main lobe with the noise floor) might require a smallerresolution bandwidth (RBW) to be u
13、sed. A good rule of thumb is to chooseRBW such that there is no more than 1 dB change in the signal PSD across theRBW.For all values of framed data rate available in the STU-R, the following set ofPSD masks (PSDMASKSHDSL(f) shall be selectable:=)( fPSDMASKSHDSL+MHz12MHz3.184,dBm50of window MHz1, the
14、inpower max with ,peak dBm/Hz90MHz184.3,dBm90)105683.0( log 10of window MHz1, theinpower max with ,peak dBm/Hz90,1011sin1135int5.1410int10)(2322ffffffffffffNffNfffKfetdBMaskedOffsOrderdBsymsymsymSHDSLwhere MaskedOffsetdB(f) is defined as:()+=dBdBdBdBffffffffOffsetdBMasked3333,dB1,4.01fintis the freq
15、uency where the two functions governing PSDMASKSHDSL(f) intersect in therange 0 to fsym. KSHDSL, Order, N, fsym, and f3dBare defined in tables 39 and 40. R is thepayload bit rate. The variables f, fsym, fint, and f3dBin the equations are in units of Hz.TIA-968-B ErrataThis page was intentionally left blank.# # #
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