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[[File:P_ID1983__Bei_A_4_8.png|right|frame|Übersicht zu HSDPA und HSUPA]]
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[[File:P_ID1983__Bei_A_4_8.png|right|frame|Overview of HSDPA and HSUPA]]
Um eine bessere Dienstgüte zu erreichen, wurde der UMTS–Standard Release  $99$  weiter entwickelt. Die wichtigsten Weiterentwicklungen waren:
+
To achieve better quality of service,  the UMTS Release 99 standard was further developed.   
*UMTS Release  $5$  mit  '''HSDPA''' (2002),
 
*UMTS Release  $6$  mit  '''HSUPA''' (2004).
 
  
 +
The most important further developments were:
 +
*UMTS Release 5  with  $\rm HSDPA$  $($2002$)$,
  
Zusammengefasst werden diese Entwicklungen als  '''High–Speed Packet Access'''  (HSPA).
+
*UMTS Release  6  with  $\rm HUDPA$  $($2004$)$.
  
Das Schaubild zeigt einige Eigenschaften von HSDPA und HSUPA, die besonders zur Steigerung der Leistungsfähigkeit beitragen:
 
*Beide nutzen  ''Hybrid Automatic Repeat Request''  (HARQ) und  ''Node B Scheduling''.
 
*Mit HSDPA wurde der Hochgeschwindigkeits–Transportkanal  '''HS–PDSCH'''  (''High–Speed Physical Downlink Shared Channel'')  neu eingeführt, der von mehreren Nutzern gemeinsam belegt wird und die simultane Übertragung gleicher Daten an viele Teilnehmer ermöglicht.
 
*Beim HSUPA–Standard gibt es den zusätzlichen Transportkanal  ''Enhanced Dedicated Channel''  ('''E–DCH'''). Dieser minimiert unter anderem den negativen Einfluss von Anwendungen mit sehr intensivem bzw. stark unterschiedlichem Datenaufkommen.
 
*Bei HSPA wird eine adaptive Modulation und Codierung verwendet; die Übertragungsrate wird entsprechend angepasst.
 
*Bei guten Bedingungen wird eine  $\rm 16–QAM$  $(4$ bit pro Symbol$)$  bzw.  $64$–QAM  $(6$ bit pro Symbol$)$  verwendet, bei schlechteren Bedingungen nur  $\rm 4–QAM\  (QPSK)$.
 
*Die maximal erreichbare Bitrate hängt von der Leistungsfähigkeit des Empfängers ab, aber auch vom  ''Transportformat und den Ressourcenkombinationen''  $ \text{(TFRC)}$.
 
  
 +
Collectively,  these developments are known as  »'''High-Speed Packet Access'''«  $\rm (HSPA)$.
  
Von den zehn spezifizierten TFRC–Klassen seien hier willkürlich nur einige aufgeführt:
+
The chart shows some of the features of HSDPA and HSUPA that particularly contribute to the increase in performance:
*$\text{TFRC2:}$   $\rm 4–QAM\  (QPSK)$  mit Coderate  $R_{\rm C} =1/2$   ⇒   Bitrate $240 \ \rm kbit/s$,
+
#Both use  »'''Hybrid Automatic Repeat Request'''«  $\rm (HARQ)$  and  »'''Node B Scheduling'''«.
*$\text{TFRC4:}$   $\rm 16–QAM$, mit Coderate  $R_{\rm C} =1/2$   ⇒   Bitrate $480 \ \rm kbit/s$,
+
#With HSDPA,  the high-speed transport channel  »'''HS-PDSCH'''«  $($"High-Speed Physical Downlink Shared Channel"$)$  was newly introduced,  which is shared by multiple users and allows simultaneous transmission of the same data to many subscribers.
*$\text{TFRC8:}$   $\rm 64–QAM$, mit Coderate  $R_{\rm C} =3/4$   ⇒   Bitrate $1080 \ \rm kbit/s$.
+
#In the HSUPA standard,  there is the additional transport channel  »'''Enhanced Dedicated Channel'''«  $($'''E-DCH'''$)$. Among other things,  this minimizes the negative impact of applications with very intensive or highly varying data volumes.
 +
#In HSPA,  adaptive modulation and coding is used;  the transmission rate is adjusted accordingly.
 +
#In good conditions,  a  $\text{16-QAM}$  $(4$  bit per symbol$)$  or  $\text{64-QAM}$    $(6$ bit per symbol$)$  is used,  in worse conditions only  $\text{4-QAM (QPSK)}$.
 +
#The maximum achievable bit rate depends on receiver performance,  but also on  "transport format and resource combinations"  $\text{(TFRC)}$.
  
  
Auf andere TFRC–Klassen wird in den Teilaufgaben  '''(4)'''  und  '''(5)'''  eingegangen.
+
Of the ten specified TFRC classes,  only a few are listed here arbitrarily:
 +
*$\text{TFRC2:}$     $\text{4-QAM (QPSK)}$   with code rate   $R_{\rm C} =1/2$   ⇒   bit rate:  $240 \hspace{0.15cm} \rm kbit/s$,
  
 +
*$\text{TFRC4:}$     $\text{16-QAM}$    with code rate   $R_{\rm C} =1/2$   ⇒   bit rate:  $480 \hspace{0.15cm} \rm kbit/s$,
  
 +
*$\text{TFRC8:}$     $\text{64-QAM}$   with code rate  $R_{\rm C} =3/4$   ⇒   bit rate:  $1080 \hspace{0.15cm} \rm kbit/s$.
  
  
 +
Other TFRC classes are discussed in the subtasks  '''(4)'''  and  '''(5)''' .
  
  
''Hinweis:''
+
<u>Hints:</u>:&nbsp; This exercise belongs to the chapter&nbsp; [[Examples_of_Communication_Systems/Further_Developments_of_UMTS|"Further Developments of UMTS"]].
*Die Aufgabe gehört zum Kapitel&nbsp; [[Examples_of_Communication_Systems/Weiterentwicklungen_von_UMTS|Weiterentwicklungen von UMTS]].
 
 
   
 
   
  
  
===Fragebogen===
+
===Questions===
  
 
<quiz display=simple>
 
<quiz display=simple>
{Welcher Standard erlaubt die höchsten Datenraten?
+
{Which standard allows the highest data rates?
 
|type="[]"}
 
|type="[]"}
- UMTS (Release&nbsp; $99$),
+
- UMTS&nbsp; $($Release 99$)$,
 
+ HSDPA,
 
+ HSDPA,
 
- HSUPA.
 
- HSUPA.
  
{Was versteht man unter&nbsp; $\rm HARQ$&nbsp; und was wird damit erreicht?
+
{What is meant by&nbsp; "$\rm HARQ$"&nbsp; and what does it achieve?
 
|type="[]"}
 
|type="[]"}
+ Die Übertragung eines Rahmens startet erst nach Auswertung der gesendeten Kontrolldaten durch den Empfänger.
+
+ Transmission of a frame starts only after evaluation of the sent control data by the receiver.
+ Bei fehlerfreier Übertragung wird eine positive Quittung versendet, ansonsten ein NACK&nbsp; (''Non Acknowledgement'').
+
+ If the transmission is error-free,&nbsp; a positive&nbsp; "acknowledgement"&nbsp; is sent,&nbsp; otherwise a NACK&nbsp; $($"Non acknowledgement"$)$.
- Die erreichbare Datenrate wird durch HARQ herabgesetzt, wenn man vom AWGN–Kanal und gleichem&nbsp; $E_{\rm B}/N_{0}$ ausgeht.
+
- The achievable data rate is lowered by HARQ,&nbsp; assuming the AWGN channel and equal&nbsp; $E_{\rm B}/N_{0}$.
  
{Was versteht man unter&nbsp; $\rm Node \ B \ Scheduling$&nbsp;? Was erreicht man damit?
+
{What is meant by&nbsp; "$\rm Node \ B \ Scheduling$"&nbsp;? What can be achieved with it?
 
|type="[]"}
 
|type="[]"}
+ Zuweisung von Prioritäten an die einzelnen Datenrahmen.
+
+ Assigning priorities to the individual data frames.
+ Der Nutzer mit höchster Priorität bekommt den besten Kanal.
+
+ The user with the highest priority gets the best channel.
+ Durch Scheduling wird die Zellenkapazität signifikant größer.
+
+ Scheduling significantly increases the cell capacity.
  
{Wie groß ist die Bitrate von&nbsp; $\rm TFRC3$&nbsp; $($QPSK, Coderate&nbsp; $R_{\rm C} =3/4)$&nbsp;?
+
{What is the bit rate of&nbsp; $\rm TFRC3$&nbsp; $($QPSK,&nbsp; code rate&nbsp; $R_{\rm C} =3/4)$&nbsp;?
 
|type="{}"}
 
|type="{}"}
 
$R_{\rm B} \ = \ $ { 360 3% } $\ \rm kbit/s$
 
$R_{\rm B} \ = \ $ { 360 3% } $\ \rm kbit/s$
  
{Wie groß ist die Bitrate von&nbsp; $\rm TFRC10$&nbsp; $($64–QAM, Coderate&nbsp; $R_{\rm C} =1)$&nbsp;?
+
{What is the bit rate of&nbsp; $\rm TFRC10$&nbsp; $($64-QAM,&nbsp; code rate&nbsp; $R_{\rm C} =1)$&nbsp;?
 
|type="{}"}
 
|type="{}"}
 
$R_{\rm B} \ = \ $ { 1440 3% } $\ \rm kbit/s$
 
$R_{\rm B} \ = \ $ { 1440 3% } $\ \rm kbit/s$
 
</quiz>
 
</quiz>
  
===Musterlösung===
+
===Solution===
 
{{ML-Kopf}}
 
{{ML-Kopf}}
  
'''(1)'''&nbsp; Richtig ist der <u>Lösungsvorschlag 2</u>.:
+
'''(1)'''&nbsp; Correct is&nbsp; <u>solution 2</u>:
*Die Datenübertragungsrate beträgt beim herkömmlichen UMTS zwischen&nbsp; $144 \ \rm kbit/s$&nbsp; und&nbsp; $2 \ \rm Mbit/s$.
+
*For conventional UMTS,&nbsp; the data transfer rate is between&nbsp; $144 \ \rm kbit/s$&nbsp; and&nbsp; $2 \ \rm Mbit/s$.  
*Für den HSDPA (die Abkürzung steht für ''High–Speed Downlink Packet Access'') werden Datenraten zwischen&nbsp; $500 \ \rm kbit/s$&nbsp; und&nbsp; $3.6 \ \rm Mbit/s$&nbsp; angegeben, und als Grenzwert sogar&nbsp; $14.4 \ \rm Mbit/s$.
 
*HSUPA (''High–Speed Uplink Packet Access'') bezieht sich dagegen auf den Aufwärtskanal, der stets eine kleinere Datenrate als der Downlink aufweist. In der Praxis werden Datenraten bis&nbsp; $800 \ \rm kbit/s$&nbsp; erreicht, der theoretische Grenzwert liegt bei&nbsp; $5.8 \ \rm Mbit/s$.  
 
  
 +
*For HSDPA&nbsp; $($the abbreviation stands for&nbsp; "High-Speed Downlink Packet Access"$)$,&nbsp; data rates between&nbsp; $500 \ \rm kbit/s$&nbsp; and&nbsp; $3.6 \ \rm Mbit/s$&nbsp; are specified,&nbsp; and as a limit even&nbsp; $14.4 \ \rm Mbit/s$.
  
 +
*HSUPA&nbsp; $($"High-Speed Uplink Packet Access"$)$&nbsp; refers to the uplink channel,&nbsp; which always has a lower data rate than the downlink.&nbsp; In practice,&nbsp; data rates up to&nbsp; $800 \ \rm kbit/s$&nbsp; are achieved,&nbsp; the theoretical limit being&nbsp; $5.8 \ \rm Mbit/s$.
  
'''(2)'''&nbsp; Die <u>beiden ersten Aussagen</u> sind richtig:  
+
 
*Eine detaillierte Beschreibung des HARQ–Verfahrens finden Sie im&nbsp; [[Examples_of_Communication_Systems/Weiterentwicklungen_von_UMTS#HARQ.E2.80.93Verfahren_und_Node_B_Scheduling|Theorieteil]].  
+
 
*Nicht richtig ist dagegen die Aussage 3. Das&nbsp; [[Examples_of_Communication_Systems/Weiterentwicklungen_von_UMTS#HARQ.E2.80.93Verfahren_und_Node_B_Scheduling|Diagramm]]&nbsp; im Theorieteil zeigt vielmehr, dass für&nbsp; $10 \cdot {\rm lg} E_{\rm B}/N_{0} = 0 \ \rm dB$&nbsp; (AWGN–Kanal) die Datenrate von&nbsp; $600 \ \rm kbit/s$&nbsp; auf nahezu&nbsp; $800 \ \rm kbit/s$&nbsp; vergrößert werden kann.  
+
'''(2)'''&nbsp; The&nbsp; <u>first two statements</u>&nbsp; are correct:  
*Unterhalb von&nbsp; $-2 \ \rm dB$&nbsp; ist ausschließlich mit HARQ eine brauchbare Übertragung möglich. Bei guten Kanälen&nbsp; $(E_{\rm B}/N_{0} > 2&nbsp; \ \rm dB)$ ist HARQ dagegen nicht erforderlich.
+
*For a detailed description of the HARQ procedure,&nbsp; see the&nbsp; [[Examples_of_Communication_Systems/Further_Developments_of_UMTS#HARQ_procedure_and_.22Node_B_Scheduling.22|"theory section"]].
 +
 +
*In contrast,&nbsp; statement 3 is not correct.&nbsp; The&nbsp; [[Examples_of_Communication_Systems/Further_Developments_of_UMTS#HARQ_procedure_and_.22Node_B_Scheduling.22 |"diagram"]]&nbsp; in the theory part rather shows that for&nbsp; $10 \cdot {\rm lg}\ E_{\rm B}/N_{0} = 0 \ \rm dB$&nbsp; $($AWGN channel$)$&nbsp; the data rate can be increased from&nbsp; $600 \ \rm kbit/s$&nbsp; to nearly&nbsp; $800 \ \rm kbit/s$.  
 +
 
 +
*Below&nbsp; $-2 \ \rm dB$,&nbsp; a&nbsp; usable transmission is only possible with HARQ.&nbsp; In contrast,&nbsp; for good channels&nbsp; $(E_{\rm B}/N_{0} > 2&nbsp; \ \rm dB)$,&nbsp; HARQ is not required.
  
  
  
'''(3)'''&nbsp; <u>Alle Aussagen sind richtig</u>. Weitere Hinweise zum ''Node B Scheduling'' finden Sie im [[Examples_of_Communication_Systems/Weiterentwicklungen_von_UMTS#HARQ.E2.80.93Verfahren_und_Node_B_Scheduling|Theorieteil]].
+
'''(3)'''&nbsp; <u>All statements are correct</u>.&nbsp; For further guidance on&nbsp; "Node B Scheduling",&nbsp; see [[Examples_of_Communication_Systems/Further_Developments_of_UMTS#HARQ_procedure_and_.22Node_B_Scheduling.22|"theory section"]].
  
  
  
'''(4)'''&nbsp; Die Bitrate&nbsp; $R_{\rm B}\hspace{0.15cm} \underline{= 360 \ \rm kbit/s}$&nbsp; ist wegen der größeren Coderate um den Faktor&nbsp; $(3/4)/(1/2) = 1.5$&nbsp; größer als die Bitrate von TFRC2.
+
'''(4)'''&nbsp; The bit rate&nbsp; $R_{\rm B}\hspace{0.15cm} \underline{= 360 \ \rm kbit/s}$&nbsp; is larger than the bit rate of TFRC2 by a factor&nbsp; $(3/4)/(1/2) = 1.5$&nbsp; because of the larger code rate.
  
  
  
'''(5)'''&nbsp;  
+
'''(5)'''&nbsp; With the code rate &nbsp; $R_{\rm C} =1$, &nbsp; QPSK&nbsp; $(2 \ \rm bit \ per \ symbol)$&nbsp; would result in the bit rate&nbsp; $480 \ \rm kbit/s$.  
*Mit der  Coderate&nbsp; $R_{\rm C} =1$&nbsp; würde sich bei QPSK&nbsp; $(2 \ \rm bit \ pro \ Symbol)$&nbsp; die Bitrate&nbsp; $480 \ \rm kbit/s$&nbsp; ergeben.  
 
  
*Bei&nbsp; $64$–QAM ($6 \ \rm bit$ pro Symbol)&nbsp; ist der Wert dreimal so groß: &nbsp; $R_{\rm B} \hspace{0.15cm}\underline{= 1440 \ \rm kbit/s}$.
+
*For&nbsp; $\text{64-QAM}$ &nbsp; $(6 \ \rm bit \ per \ symbol)$&nbsp; the value is three times: &nbsp; $R_{\rm B} \hspace{0.15cm}\underline{= 1440 \ \rm kbit/s}$.
  
 
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[[Category:Examples of Communication Systems: Exercises|^4.4 Weiterentwicklungen von UMTS
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[[Category:Examples of Communication Systems: Exercises|^4.4 Further Developments of
 
^]]
 
^]]

Latest revision as of 17:22, 4 March 2023

Overview of HSDPA and HSUPA

To achieve better quality of service,  the UMTS Release 99 standard was further developed. 

The most important further developments were:

  • UMTS Release 5  with  $\rm HSDPA$  $($2002$)$,
  • UMTS Release  6  with  $\rm HUDPA$  $($2004$)$.


Collectively,  these developments are known as  »High-Speed Packet Access«  $\rm (HSPA)$.

The chart shows some of the features of HSDPA and HSUPA that particularly contribute to the increase in performance:

  1. Both use  »Hybrid Automatic Repeat Request«  $\rm (HARQ)$  and  »Node B Scheduling«.
  2. With HSDPA,  the high-speed transport channel  »HS-PDSCH«  $($"High-Speed Physical Downlink Shared Channel"$)$  was newly introduced,  which is shared by multiple users and allows simultaneous transmission of the same data to many subscribers.
  3. In the HSUPA standard,  there is the additional transport channel  »Enhanced Dedicated Channel«  $($E-DCH$)$. Among other things,  this minimizes the negative impact of applications with very intensive or highly varying data volumes.
  4. In HSPA,  adaptive modulation and coding is used;  the transmission rate is adjusted accordingly.
  5. In good conditions,  a  $\text{16-QAM}$  $(4$  bit per symbol$)$  or  $\text{64-QAM}$   $(6$ bit per symbol$)$  is used,  in worse conditions only  $\text{4-QAM (QPSK)}$.
  6. The maximum achievable bit rate depends on receiver performance,  but also on  "transport format and resource combinations"  $\text{(TFRC)}$.


Of the ten specified TFRC classes,  only a few are listed here arbitrarily:

  • $\text{TFRC2:}$     $\text{4-QAM (QPSK)}$   with code rate   $R_{\rm C} =1/2$   ⇒   bit rate:  $240 \hspace{0.15cm} \rm kbit/s$,
  • $\text{TFRC4:}$     $\text{16-QAM}$   with code rate   $R_{\rm C} =1/2$   ⇒   bit rate:  $480 \hspace{0.15cm} \rm kbit/s$,
  • $\text{TFRC8:}$     $\text{64-QAM}$   with code rate  $R_{\rm C} =3/4$   ⇒   bit rate:  $1080 \hspace{0.15cm} \rm kbit/s$.


Other TFRC classes are discussed in the subtasks  (4)  and  (5) .


Hints::  This exercise belongs to the chapter  "Further Developments of UMTS".


Questions

1

Which standard allows the highest data rates?

UMTS  $($Release 99$)$,
HSDPA,
HSUPA.

2

What is meant by  "$\rm HARQ$"  and what does it achieve?

Transmission of a frame starts only after evaluation of the sent control data by the receiver.
If the transmission is error-free,  a positive  "acknowledgement"  is sent,  otherwise a NACK  $($"Non acknowledgement"$)$.
The achievable data rate is lowered by HARQ,  assuming the AWGN channel and equal  $E_{\rm B}/N_{0}$.

3

What is meant by  "$\rm Node \ B \ Scheduling$" ? What can be achieved with it?

Assigning priorities to the individual data frames.
The user with the highest priority gets the best channel.
Scheduling significantly increases the cell capacity.

4

What is the bit rate of  $\rm TFRC3$  $($QPSK,  code rate  $R_{\rm C} =3/4)$ ?

$R_{\rm B} \ = \ $

$\ \rm kbit/s$

5

What is the bit rate of  $\rm TFRC10$  $($64-QAM,  code rate  $R_{\rm C} =1)$ ?

$R_{\rm B} \ = \ $

$\ \rm kbit/s$


Solution

(1)  Correct is  solution 2:

  • For conventional UMTS,  the data transfer rate is between  $144 \ \rm kbit/s$  and  $2 \ \rm Mbit/s$.
  • For HSDPA  $($the abbreviation stands for  "High-Speed Downlink Packet Access"$)$,  data rates between  $500 \ \rm kbit/s$  and  $3.6 \ \rm Mbit/s$  are specified,  and as a limit even  $14.4 \ \rm Mbit/s$.
  • HSUPA  $($"High-Speed Uplink Packet Access"$)$  refers to the uplink channel,  which always has a lower data rate than the downlink.  In practice,  data rates up to  $800 \ \rm kbit/s$  are achieved,  the theoretical limit being  $5.8 \ \rm Mbit/s$.


(2)  The  first two statements  are correct:

  • In contrast,  statement 3 is not correct.  The  "diagram"  in the theory part rather shows that for  $10 \cdot {\rm lg}\ E_{\rm B}/N_{0} = 0 \ \rm dB$  $($AWGN channel$)$  the data rate can be increased from  $600 \ \rm kbit/s$  to nearly  $800 \ \rm kbit/s$.
  • Below  $-2 \ \rm dB$,  a  usable transmission is only possible with HARQ.  In contrast,  for good channels  $(E_{\rm B}/N_{0} > 2  \ \rm dB)$,  HARQ is not required.


(3)  All statements are correct.  For further guidance on  "Node B Scheduling",  see "theory section".


(4)  The bit rate  $R_{\rm B}\hspace{0.15cm} \underline{= 360 \ \rm kbit/s}$  is larger than the bit rate of TFRC2 by a factor  $(3/4)/(1/2) = 1.5$  because of the larger code rate.


(5)  With the code rate   $R_{\rm C} =1$,   QPSK  $(2 \ \rm bit \ per \ symbol)$  would result in the bit rate  $480 \ \rm kbit/s$.

  • For  $\text{64-QAM}$   $(6 \ \rm bit \ per \ symbol)$  the value is three times:   $R_{\rm B} \hspace{0.15cm}\underline{= 1440 \ \rm kbit/s}$.