Examples of Communication Systems/Further Developments of the GSM - Revision history

Guenter at 14:14, 20 February 2023

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Guenter at 15:12, 28 January 2023

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Guenter at 15:09, 28 January 2023

2023-01-28T15:09:32Z

@@ Line 130: / Line 130: @@
 The smallest possible data rate is thus &nbsp; $9.05\ \rm kbit/s$&nbsp; $($only one time slot$)$,&nbsp; the maximum&nbsp; $171.2\ \rm kbit/s$&nbsp; $($eight time slots$)$.&nbsp; However,&nbsp; this theoretical speed was not achieved in practice,&nbsp; since most GPRS phones only support in 2007 a maximum net data rate of&nbsp; $13.4\ \rm kbit/s$&nbsp; $\text{(CS &ndash; 2})$. The graphic refer to this combination:
-[[File:EN_Bei_T_3_5_S5a_v4.png|right|frame|Channel encoding in GPRS '''KORREKTUR: punkturing''']]
+[[File:EN_Bei_T_3_5_S5a_neu.png|right|frame|Channel encoding in GPRS]]
 #&nbsp; The&nbsp; $268$&nbsp; information bits are first supplemented by six precoded bits of the&nbsp; "Uplink State Flag"&nbsp; $\rm (USF)$, &nbsp;$16$&nbsp; parity bits of the&nbsp; "Block Check Sequence"&nbsp; $\rm (BCS)$&nbsp; and four tail bits&nbsp; $(0000)$.&nbsp; The latter are necessary for the termination of the convolutional codes.<br><br>

@@ Line 59: / Line 59: @@
 A GPRS user benefits from shorter access times and the higher data rate&nbsp; $($to&nbsp; $21.4 \ \rm kbit/s)$&nbsp; compared
-[[File:EN_Bei_T_3_5_S3.png|right|frame|GPRS system architecture '''KORREKTUR: permission to''']]
+[[File:EN_Bei_T_3_5_S3_v2.png|right|frame|GPRS system architecture]]
 *to conventional GSM&nbsp; $(9.6 \ \rm kbit/s)$&nbsp;

@@ Line 169: / Line 169: @@
 #&nbsp; Like GSM/GPRS,&nbsp; the first four schemes use the GMSK modulation with one bit of information per channel use,&nbsp; while&nbsp; "8-PSK"&nbsp; is used in&nbsp; MCS-5, ... ,&nbsp; MCS-9,&nbsp; and thus three bits per symbol are transmitted.
 #&nbsp; The smaller the code rate,&nbsp; the greater the added redundancy and thus the data security.&nbsp; In particular,&nbsp; between&nbsp; MCS-4&nbsp; $(R_{\rm C} = 1)$&nbsp; and&nbsp; MCS-5&nbsp; $(R_{\rm C} = 0.37)$&nbsp; the code rate decreases significantly due to the more favorable modulation mode despite the higher net data rate.
-#&nbsp; The most elaborate mode&nbsp; $($MCS-9$)$&nbsp; offers a data rate of&nbsp; $59.2\ \rm kbit/s$&nbsp; andallows the simultaneous occupation of eight time slots,&nbsp; which would mean a maximum net data rate of&nbsp; $473.6\ \rm kbit/s$.&nbsp; However,&nbsp; this mode&nbsp; $($with $R_{\rm C} = 1)$&nbsp; is only applicable under extremely good conditions.
+#&nbsp; The most elaborate mode&nbsp; $($MCS-9$)$&nbsp; offers a data rate of&nbsp; $59.2\ \rm kbit/s$&nbsp; and allows the simultaneous occupation of eight time slots,&nbsp; which would mean a maximum net data rate of&nbsp; $473.6\ \rm kbit/s$.&nbsp; However,&nbsp; this mode&nbsp; $($with $R_{\rm C} = 1)$&nbsp; is only applicable under extremely good conditions.
 #&nbsp; With&nbsp; MCS-8&nbsp; and seven time slots you can already reach&nbsp; $380.8 \ \rm kbit/s$&nbsp; and you are thus in the range of the 3G mobile radio standard&nbsp; $\rm UMTS$,&nbsp; which currently offers&nbsp; $384 \ \rm kbit/s$.
 #&nbsp; EDGE uses the same frequencies as GSM,&nbsp; which is why this technology was particularly interesting for operators with existing GSM infrastructure who did not acquire any of the more expensive UMTS licenses and still wanted to offer a sufficiently high data rate.

@@ Line 130: / Line 130: @@
 The smallest possible data rate is thus &nbsp; $9.05\ \rm kbit/s$&nbsp; $($only one time slot$)$,&nbsp; the maximum&nbsp; $171.2\ \rm kbit/s$&nbsp; $($eight time slots$)$.&nbsp; However,&nbsp; this theoretical speed was not achieved in practice,&nbsp; since most GPRS phones only support in 2007 a maximum net data rate of&nbsp; $13.4\ \rm kbit/s$&nbsp; $\text{(CS &ndash; 2})$. The graphic refer to this combination:
-[[File:EN_Bei_T_3_5_S5a_v4.png|right|frame|Channel encoding in GPRS]]
+[[File:EN_Bei_T_3_5_S5a_v4.png|right|frame|Channel encoding in GPRS '''KORREKTUR: punkturing''']]
 #&nbsp; The&nbsp; $268$&nbsp; information bits are first supplemented by six precoded bits of the&nbsp; "Uplink State Flag"&nbsp; $\rm (USF)$, &nbsp;$16$&nbsp; parity bits of the&nbsp; "Block Check Sequence"&nbsp; $\rm (BCS)$&nbsp; and four tail bits&nbsp; $(0000)$.&nbsp; The latter are necessary for the termination of the convolutional codes.<br><br>

@@ Line 59: / Line 59: @@
 A GPRS user benefits from shorter access times and the higher data rate&nbsp; $($to&nbsp; $21.4 \ \rm kbit/s)$&nbsp; compared
-[[File:EN_Bei_T_3_5_S3.png|right|frame|GPRS system architecture]]
+[[File:EN_Bei_T_3_5_S3.png|right|frame|GPRS system architecture '''KORREKTUR: permission to''']]
 *to conventional GSM&nbsp; $(9.6 \ \rm kbit/s)$&nbsp;

@@ Line 9: / Line 9: @@
 ==The different phases of the GSM standardization==
 <br>
-GSM was originally designed and developed as a pan-European mobile communications network,&nbsp; primarily for telephone calls and fax.&nbsp; Data transmission at a constant low data rate was secondary.&nbsp; The GSM standard was further developed in&nbsp; '''various phases'''&nbsp; after its presentation.&nbsp; The&nbsp; $\rm GSM$&nbsp; system described so far in the third main chapter is limited to the first two phases.
+GSM was originally designed and developed as a pan-European mobile communications network,&nbsp; primarily for telephone calls and fax.&nbsp; Data transmission at a constant low data rate was secondary.&nbsp; The GSM standard was further developed in&nbsp; &raquo;'''various phases'''&laquo;&nbsp; after its presentation.&nbsp; The&nbsp; $\rm GSM$&nbsp; system described so far in the third main chapter is limited to the first two phases.
-&rArr; &nbsp; The&nbsp; '''&raquo;phase 1&laquo;'''&nbsp; included only basic teleservices and a few additional services that could be offered on a mandatory basis by all network operators at that time when GSM was launched in 1991.<br>
+&rArr; &nbsp; The&nbsp; &raquo;'''phase 1'''&laquo;&nbsp; included only basic teleservices and a few additional services that could be offered on a mandatory basis by all network operators at that time when GSM was launched in 1991.<br>
-&rArr; &nbsp; The standardization of the&nbsp; '''&raquo;phase 2&laquo;'''&nbsp; in the years from 1995 to 1997 already included the first further developments of the GSM standard.&nbsp; As a result,&nbsp; the additional services known from&nbsp; [[Examples_of_Communication_Systems/General_Description_of_ISDN|"ISDN"]]&nbsp; were also gradually made available for GSM and supplemented by some new features,&nbsp; such as&nbsp; "call waiting"&nbsp; or&nbsp; "hold".
+&rArr; &nbsp; The standardization of the&nbsp; &raquo;'''phase 2'''&laquo;&nbsp; in the years from 1995 to 1997 already included the first further developments of the GSM standard.&nbsp; As a result,&nbsp; the additional services known from&nbsp; [[Examples_of_Communication_Systems/General_Description_of_ISDN|$\text{ISDN}$]]&nbsp; were also gradually made available for GSM and supplemented by some new features,&nbsp; such as&nbsp; "call waiting"&nbsp; or&nbsp; "hold".
-&rArr; &nbsp; In the years 1997-2000,&nbsp; new data services with higher data rates were developed,&nbsp; which are allocated to the&nbsp; '''&raquo;phase 2+&laquo;'''.&nbsp; These new data services include:
+&rArr; &nbsp; In the years 1997-2000,&nbsp; new data services with higher data rates were developed,&nbsp; which are allocated to the&nbsp; &raquo;'''phase 2+'''&laquo;.&nbsp; These new data services include:
-#&nbsp; [[Examples_of_Communication_Systems/Further_Developments_of_the_GSM#High_Speed_Circuit.E2.80.93Switched_Data_.28HSCSD.29|"High Speed Circuit-Switched Data"]]&nbsp; $\rm (HSCSD)$,
+#&nbsp; [[Examples_of_Communication_Systems/Further_Developments_of_the_GSM#High_Speed_Circuit.E2.80.93Switched_Data_.28HSCSD.29|$\text{High Speed Circuit-Switched Data}$]]&nbsp; $\rm (HSCSD)$,
-#&nbsp; [[Examples_of_Communication_Systems/Further_Developments_of_the_GSM#General_Packet_Radio_Service_.28GPRS.29|"General Packet Radio Service"]]&nbsp; $\rm (GPRS)$,
+#&nbsp; [[Examples_of_Communication_Systems/Further_Developments_of_the_GSM#General_Packet_Radio_Service_.28GPRS.29|$\text{General Packet Radio Service}$]]&nbsp; $\rm (GPRS)$,
-#&nbsp; [[Examples_of_Communication_Systems/Further_Developments_of_the_GSM#Enhanced_Data_Rates_for_GSM_Evolution|"Enhanced Data Rates for GSM Evolution"]]&nbsp; $\rm (EDGE)$.
+#&nbsp; [[Examples_of_Communication_Systems/Further_Developments_of_the_GSM#Enhanced_Data_Rates_for_GSM_Evolution|$\text{Enhanced Data Rates for GSM Evolution}$]]&nbsp; $\rm (EDGE)$.
@@ Line 24: / Line 24: @@
 * GSM is a second generation&nbsp; $\rm (2G)$&nbsp; mobile communications system,&nbsp; independent of the standardization phase.
-*The third generation&nbsp; $\rm (3G)$&nbsp; includes&nbsp; [[Examples_of_Communication_Systems/General_Description_of_UMTS|"UMTS"]].&nbsp;  This standard enabled significantly higher data transmission rates than were possible with GSM.
+*The third generation&nbsp; $\rm (3G)$&nbsp; includes&nbsp; [[Examples_of_Communication_Systems/General_Description_of_UMTS|$\text{UMTS}$]].&nbsp;  This standard enabled significantly higher data transmission rates than were possible with GSM.
 *"Phase 2+"&nbsp; systems are in terms of performance between&nbsp; $\rm 2G$&nbsp; and&nbsp; $\rm 2G$.&nbsp; That is why we speak of&nbsp; $\rm 2.5G$.&nbsp; The innovations of the&nbsp; "phase 2+"&nbsp; affect almost all aspects of GSM,&nbsp;  from&nbsp; "radio transmission"&nbsp; to&nbsp; "call control".
@@ Line 33: / Line 33: @@
 ==High Speed Circuit–Switched Data (HSCSD)==
 <br>
-The GSM data transmission standard&nbsp; '''&raquo;high speed circuit-switched data&laquo;'''&nbsp; $\rm (HSCSD)$,&nbsp; introduced in 1999,&nbsp; allowed the user data rate per connection to be increased from&nbsp; $9.6 \ \rm kbit/s$&nbsp; to&nbsp; $14.4 \ \rm kbit/s$&nbsp; when transmission conditions permitted.
+The GSM data transmission standard&nbsp; &raquo;'''high speed circuit-switched data'''&laquo;&nbsp; $\rm (HSCSD)$,&nbsp; introduced in 1999,&nbsp; allowed the user data rate per connection to be increased from&nbsp; $9.6 \ \rm kbit/s$&nbsp; to&nbsp; $14.4 \ \rm kbit/s$&nbsp; when transmission conditions permitted.
 *By bundling several adjacent time slots,&nbsp; the data rate could be increased even further.
@@ Line 52: / Line 52: @@
 ==General Packet Radio Service (GPRS)==
 <br>
-With the GSM extension&nbsp; '''&raquo;general packet radio service&laquo;'''&nbsp; $\rm (GPRS)$,&nbsp; packet-switched data transmission was made possible for the first time in 2000.
+With the GSM extension&nbsp; &raquo;'''general packet radio service'''&laquo;&nbsp; $\rm (GPRS)$,&nbsp; packet-switched data transmission was made possible for the first time in 2000.
 *GPRS supports a large number of protocols&nbsp; $($Internet Protocol,&nbsp; X.25,&nbsp; Datex-P, etc.$)$&nbsp; and allows mobile subscribers to communicate with external data networks&nbsp; $($the internet or internal company intranets$)$.
@@ Line 81: / Line 81: @@
 The additional GPRS components&nbsp; $($highlighted by red circles in the diagram$)$&nbsp;  are explained here only in bullet points:
-#The&nbsp; '''&raquo;GPRS Support Nodes&laquo;'''&nbsp; $\rm (GSN)$&nbsp; are responsible for the transmission and traffic routing  of data packets between the mobile stations and the external packet-switched data networks.&nbsp; Here,&nbsp; a distinction is made between SGSN and GGSN,&nbsp; which communicate with each other via an IP-based GPRS backbone network.<br><br>
+#The&nbsp; &raquo;'''GPRS Support Nodes'''&laquo;&nbsp; $\rm (GSN)$&nbsp; are responsible for the transmission and traffic routing  of data packets between the mobile stations and the external packet-switched data networks.&nbsp; Here,&nbsp; a distinction is made between SGSN and GGSN,&nbsp; which communicate with each other via an IP-based GPRS backbone network.<br><br>
-#The&nbsp; '''&raquo;Serving GPRS Support Node&laquo;'''&nbsp; $\rm (SGSN)$&nbsp; is responsible for mobility management and performs a similar function for packet data services as the&nbsp; '''&raquo;Mobile Switching Center&laquo;'''&nbsp; $\rm (MSC)$&nbsp; does for connection-oriented speech signals.<br><br>
+#The&nbsp; &raquo;'''Serving GPRS Support Node'''&laquo;&nbsp; $\rm (SGSN)$&nbsp; is responsible for mobility management and performs a similar function for packet data services as the&nbsp; &raquo;'''Mobile Switching Center'''&laquo;&nbsp; $\rm (MSC)$&nbsp; does for connection-oriented speech signals.<br><br>
-#The&nbsp; '''&raquo;Gateway GPRS Support Node&laquo;'''&nbsp; $\rm (GGSN)$&nbsp; is the interface to foreign packet-oriented data networks.&nbsp; It converts the GPRS packets coming from the SGSN into the appropriate protocol&nbsp; $($IP,&nbsp; X.25,&nbsp; ...$)$&nbsp; and sends them out to the&nbsp; '''&raquo;Packet Data Network&laquo;'''&nbsp; $\rm (PDN)$.
+#The&nbsp; &raquo;'''Gateway GPRS Support Node'''&laquo;&nbsp; $\rm (GGSN)$&nbsp; is the interface to foreign packet-oriented data networks.&nbsp; It converts the GPRS packets coming from the SGSN into the appropriate protocol&nbsp; $($IP,&nbsp; X.25,&nbsp; ...$)$&nbsp; and sends them out to the&nbsp; &raquo;'''Packet Data Network'''&laquo;&nbsp; $\rm (PDN)$.
@@ Line 100: / Line 100: @@
 &rArr; &nbsp; To be able to switch the GSM radio interface to packet-oriented GPRS operation,&nbsp; the logical channels had to be extended.&nbsp; Logical GPRS channels can be recognized by a preceding&nbsp; "$\rm P$",&nbsp; which indicates the packet-oriented operating mode.&nbsp; Almost for all logical GSM channels there is the corresponding GPRS equivalent:
-*The&nbsp; "Packet Data Traffic Channel"&nbsp; $\rm (PDTCH)$&nbsp; is used in GPRS as&nbsp; '''&raquo;traffic channel&laquo;'''&nbsp; for user data transfer.&nbsp; The corresponding GSM channel is called&nbsp; $\rm TCH$.
+*The&nbsp; "Packet Data Traffic Channel"&nbsp; $\rm (PDTCH)$&nbsp; is used in GPRS as&nbsp; &raquo;'''traffic channel'''&laquo;&nbsp; for user data transfer.&nbsp; The corresponding GSM channel is called&nbsp; $\rm TCH$.
-*The&nbsp; '''&raquo;signaling channels&laquo;'''&nbsp; are divided as in GSM into
+*The&nbsp; &raquo;'''signaling channels'''&laquo;&nbsp; are divided as in GSM into
 #&nbsp; the&nbsp; "Packet Broadcast Control Channel"&nbsp; $\rm (PBCCH)$,&nbsp;
 #&nbsp; the&nbsp; "'Packet Common Control Channel"&nbsp; $\rm (PCCCH)$,&nbsp;
@@ Line 141: / Line 141: @@
 == Enhanced Data Rates for GSM Evolution ==
 <br>
-The last GSM extension&nbsp; '''&raquo;Enhanced data rates for GSM evolution&laquo;'''&nbsp; $\rm (EDGE)$&nbsp; with the aim to increase the data transmission rate in GSM networks uses beside&nbsp; "Gaussian Minimum Shift Keying"&nbsp; $\rm (GMSK)$&nbsp; as additional modulation method&nbsp; "eight-level phase shift keying"&nbsp; $\text{(8-PSK)}$:
+The last GSM extension&nbsp; &raquo;'''Enhanced data rates for GSM evolution'''&laquo;&nbsp; $\rm (EDGE)$&nbsp; with the aim to increase the data transmission rate in GSM networks uses beside&nbsp; "Gaussian Minimum Shift Keying"&nbsp; $\rm (GMSK)$&nbsp; as additional modulation method&nbsp; "eight-level phase shift keying"&nbsp; $\text{(8-PSK)}$:
 *Then,&nbsp; there are eight different symbols&nbsp; $($with GMSK only two$)$,&nbsp; distinguished by different phase positions at multiples of&nbsp; $45^\circ$.&nbsp;
@@ Line 149: / Line 149: @@
 With this definition:
-* [[Examples_of_Communication_Systems/Further_Developments_of_the_GSM#High_Speed_Circuit.E2.80.93Switched_Data_.28HSCSD.29|"HSCSD"]]&nbsp; becomes&nbsp; "Enhanced Circuit Switched Data"&nbsp; $\text{(E-CSD)}$&nbsp; and
+* [[Examples_of_Communication_Systems/Further_Developments_of_the_GSM#High_Speed_Circuit.E2.80.93Switched_Data_.28HSCSD.29|$\text{HSCSD}$]]&nbsp; becomes&nbsp; "Enhanced Circuit Switched Data"&nbsp; $\text{(E-CSD)}$&nbsp; and
-*[[Examples_of_Communication_Systems/Further_Developments_of_the_GSM#General_Packet_Radio_Service_.28GPRS.29|"GPRS"]]&nbsp; becomes&nbsp; "enhanced GPRS"&nbsp; $\text{(E-GPRS)}$.
+*[[Examples_of_Communication_Systems/Further_Developments_of_the_GSM#General_Packet_Radio_Service_.28GPRS.29|$\text{GPRS}$]]&nbsp; becomes&nbsp; "enhanced GPRS"&nbsp; $\text{(E-GPRS)}$.

@@ Line 146: / Line 146: @@
 *This means:&nbsp; Three data bits can be transmitted with each symbol,&nbsp; increasing the data rate by a factor of&nbsp; $3$&nbsp; compared to GPRS.
 * [[Examples_of_Communication_Systems/Further_Developments_of_the_GSM#High_Speed_Circuit.E2.80.93Switched_Data_.28HSCSD.29|"HSCSD"]]&nbsp; becomes&nbsp; "Enhanced Circuit Switched Data"&nbsp; $\text{(E-CSD)}$&nbsp; and
-*[[Examples_of_Communication_Systems/Further_Developments_of_the_GSM#General_Packet_Radio_Service_.28GPRS.29|"GPRS"]]&nbsp; becomes&nbsp; "enhanced GPRS"&nbsp; $\text{(E-GPRS)} However, T-mobile is the only German network operator that currently (2007) offers EDGE on its network.
+*[[Examples_of_Communication_Systems/Further_Developments_of_the_GSM#General_Packet_Radio_Service_.28GPRS.29|"GPRS"]]&nbsp; becomes&nbsp; "enhanced GPRS"&nbsp; $\text{(E-GPRS)}$.
-The graphic shows the&nbsp; ''Normal Burst''&nbsp; of EDGE and E-GPRS respectively. One can see the following differences to the&nbsp; ''Normal Burst''&nbsp; of GSM:
+The graph shows the&nbsp; "normal burst"&nbsp; of&nbsp; "EDGE"&nbsp; resp.&nbsp; "E-GPRS".&nbsp; One can see the following differences to the&nbsp; "GSM Normal Burst":
-*The&nbsp; ''Normal Burst''&nbsp; in EDGE consists of&nbsp; $468.75$&nbsp; bits instead of the&nbsp; $156.25$&nbsp; bits in GSM, from which the tripling of the data rate can be seen.
+[[File:EN_Bei_T_3_5_S6a_v3.png|right|frame|Normal Burst of&nbsp; "EDGE"&nbsp; and&nbsp; "E-GPRS" ]]
-*As with GSM, there are two&nbsp; ''stealing flags''. Tailbits, training sequence and&nbsp; ''Guard Period''&nbsp; are each tripled. This leaves $57 - 3 + 2 = 173$ bits for the data field&nbsp;.
+#&nbsp; The&nbsp; EDGE normal burst&nbsp; consists of&nbsp; $468.75$&nbsp; bits instead of&nbsp; $156.25$&nbsp; bits in GSM,&nbsp;  from which the&nbsp; tripling of the data rate can be seen.<br><br>
-*Thus, channel coded data&nbsp; $($Coderate&nbsp; $R_{\rm C} =1/2)$&nbsp; per&nbsp; $576.9\ \rm &micro; s$&nbsp; are transmitted in E-GPRS in&nbsp; ''Normal Burst''&nbsp; $346$&nbsp; bits, which corresponds to a net data rate of approx.&nbsp; $60 \ \rm kbit/s$&nbsp;.
+#&nbsp; As with GSM,&nbsp; there are two&nbsp; "stealing flags".&nbsp; Tailbits,&nbsp; training sequence and&nbsp; guard period are each tripled.&nbsp; This leaves&nbsp; $57 \cdot 3 + 2 = 173$&nbsp; bits for the data field.<br><br>
-'''Modulation and Coding Schemes for E–GPRS'''
+==Modulation and Coding Schemes for E–GPRS==
-In E-GPRS, there are nine operator-selectable&nbsp; ''Modulation and Coding Schemes''&nbsp; (MCS) depending on the channel coding and modulation schemes used.
+In E-GPRS, there are used nine operator-selectable&nbsp; "Modulation and Coding Schemes"&nbsp; $\rm (MCS)$&nbsp; depending on the current modulation and channel coding.&nbsp; The table shows the possible schemes in E-GPRS.&nbsp; From this it can be seen:
-[[File:EN_Bei_T_3_5_S6b_v3.png|center|frame|Table of&nbsp; ''Modulation and Coding Schemes''&nbsp; in E-GPRS]]
+[[File:EN_Bei_T_3_5_S6b_v3.png|right|frame|Table of&nbsp; "Modulation and Coding Schemes"&nbsp; in E-GPRS]]
-The table shows the possible schemes of E-GPRS. From this it can be seen:
+#&nbsp; Like GSM/GPRS,&nbsp; the first four schemes use the GMSK modulation with one bit of information per channel use,&nbsp; while&nbsp; "8-PSK"&nbsp; is used in&nbsp; MCS-5, ... ,&nbsp; MCS-9,&nbsp; and thus three bits per symbol are transmitted.
-*The first four schemes, like GSM/GPRS, use the GMSK modulation scheme with one bit of information per channel use, while in&nbsp; $\rm MCS-5$, ... ,&nbsp; $\rm MCS-9$&nbsp; an eight-level phase modulation (8-PSK) is used and thus three bits per symbol are transmitted.
+#&nbsp; The smaller the code rate,&nbsp; the greater the added redundancy and thus the data security.&nbsp; In particular,&nbsp; between&nbsp; MCS-4&nbsp; $(R_{\rm C} = 1)$&nbsp; and&nbsp; MCS-5&nbsp; $(R_{\rm C} = 0.37)$&nbsp; the code rate decreases significantly due to the more favorable modulation mode despite the higher net data rate.
-*The smaller the code rate, the greater the added redundancy and thus the data security. In particular, between&nbsp; $\rm MCS-4$&nbsp; $(R_{\rm C} = 1)$&nbsp; and&nbsp; $\rm MCS-5$&nbsp; $(R_{\rm C} = 0.37)$&nbsp; the code rate decreases significantly due to the more favorable modulation mode despite the higher net data rate (last column).
+#&nbsp; The most elaborate mode&nbsp; $($MCS-9$)$&nbsp; offers a data rate of&nbsp; $59.2\ \rm kbit/s$&nbsp; andallows the simultaneous occupation of eight time slots,&nbsp; which would mean a maximum net data rate of&nbsp; $473.6\ \rm kbit/s$.&nbsp; However,&nbsp; this mode&nbsp; $($with $R_{\rm C} = 1)$&nbsp; is only applicable under extremely good conditions.
-*The most elaborate mode&nbsp; $\rm MCS-9$&nbsp; offers a data rate of&nbsp; $59.2 \rm kbit/s$&nbsp; according to the table and theoretically allows the simultaneous occupation of eight time slots, which would mean a maximum net data rate of&nbsp; $473.6 \rm kbit/s$&nbsp;. However, this mode&nbsp; $($with $R_{\rm C} = 1)$&nbsp; is only applicable under extremely good conditions and eight time slots are also rarely available.
+#&nbsp; With&nbsp; MCS-8&nbsp; and seven time slots you can already reach&nbsp; $380.8 \ \rm kbit/s$&nbsp; and you are thus in the range of the 3G mobile radio standard&nbsp; $\rm UMTS$,&nbsp; which currently offers&nbsp; $384 \ \rm kbit/s$.
-*With&nbsp; $\rm MCS-8$&nbsp; and seven time slots, one can after all already achieve&nbsp; $380.8 \rm kbit/s$&nbsp; and is thus in the order of magnitude of&nbsp; '''Universal Mobile Telecommunications System'''&nbsp; (UMTS), the best known standard of the third mobile radio generation, which currently offers&nbsp; $384 \rm kbit/s$&nbsp;.
+#&nbsp; EDGE uses the same frequencies as GSM,&nbsp; which is why this technology was particularly interesting for operators with existing GSM infrastructure who did not acquire any of the more expensive UMTS licenses and still wanted to offer a sufficiently high data rate.
@@ Line 179: / Line 178: @@
-==Exercises for the chapter==
+==Exercise for the chapter==
 <br>
 [[Aufgaben:Exercise_3.8:_General_Packet_Radio_Service|Exercise 3.8: General Packet Radio Service]]

← Older revision		Revision as of 15:12, 28 January 2023
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	* [[Examples_of_Communication_Systems/Further_Developments_of_the_GSM#High_Speed_Circuit.E2.80.93Switched_Data_.28HSCSD.29\|"HSCSD"]]  becomes  "Enhanced Circuit Switched Data"  $\text{(E-CSD)}$  and		* [[Examples_of_Communication_Systems/Further_Developments_of_the_GSM#High_Speed_Circuit.E2.80.93Switched_Data_.28HSCSD.29\|"HSCSD"]]  becomes  "Enhanced Circuit Switched Data"  $\text{(E-CSD)}$  and

−	*[[Examples_of_Communication_Systems/Further_Developments_of_the_GSM#~~High_Speed_Circuit~~.~~E2.80.93Switched_Data_.28HSCSD~~.29\|"~~HSCSD~~"]]  becomes  ~~''Enhanced-~~GPRS''  (E-GPRS). However, T-mobile is the only German network operator that currently (2007) offers EDGE on its network.	+	*[[Examples_of_Communication_Systems/Further_Developments_of_the_GSM#General_Packet_Radio_Service_.28GPRS.29\|"GPRS"]]  becomes  "enhanced GPRS"  $\text{(E-GPRS)} However, T-mobile is the only German network operator that currently (2007) offers EDGE on its network.

@@ Line 150: / Line 150: @@
 With the definition of EDGE:
-* HSCSD becomes&nbsp; "Enhanced Circuit Switched Data"&nbsp; $\text{(E-CSD)}$&nbsp; and
+* [[Examples_of_Communication_Systems/Further_Developments_of_the_GSM#High_Speed_Circuit.E2.80.93Switched_Data_.28HSCSD.29|"HSCSD"]]&nbsp; becomes&nbsp; "Enhanced Circuit Switched Data"&nbsp; $\text{(E-CSD)}$&nbsp; and
-*GPRS becomes&nbsp; ''Enhanced-GPRS''&nbsp; (E-GPRS). However, T-mobile is the only German network operator that currently (2007) offers EDGE on its network.
+*[[Examples_of_Communication_Systems/Further_Developments_of_the_GSM#High_Speed_Circuit.E2.80.93Switched_Data_.28HSCSD.29|"HSCSD"]]&nbsp; becomes&nbsp; ''Enhanced-GPRS''&nbsp; (E-GPRS). However, T-mobile is the only German network operator that currently (2007) offers EDGE on its network.