Mobile Communications/Characteristics of UMTS - Revision history

Maintenance script: Add German interlanguage link

2026-03-16T12:28:02Z

Add German interlanguage link

Guenter at 16:44, 20 February 2023

2023-02-20T16:44:47Z

← Older revision		Revision as of 18:44, 20 February 2023
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	⇒   The  "Core Network"  $\rm (CN)$  takes over the switching of the data within the UMTS network.  For this purpose, it contains the following hardware and software components at  "circuit-switching" :		⇒   The  "Core Network"  $\rm (CN)$  takes over the switching of the data within the UMTS network.  For this purpose, it contains the following hardware and software components at  "circuit-switching" :
	[[File:~~EN_Mob_T_3_4_S3~~.png\|right\|frame\|UMTS access level  $($with  "circuit-switching"$)$ ~~''': KORREKTUR'''~~\|class=fit]]		[[File:EN_Mob_T_3_4_S3_v2.png\|right\|frame\|UMTS access level  $($with  "circuit-switching"$)$\|class=fit]]
	:*The  "Mobile Switching Center"  $\rm (MSC)$  is responsible for localization and authentication, routing of calls, handover and encryption of user data.<br>		:*The  "Mobile Switching Center"  $\rm (MSC)$  is responsible for localization and authentication, routing of calls, handover and encryption of user data.<br>

Guenter at 13:45, 20 February 2023

2023-02-20T13:45:23Z

← Older revision		Revision as of 15:45, 20 February 2023
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	:*The  "Radio Network Controller"  $\rm (RNC)$  is responsible for controlling the base stations.  It is also responsible within the cells for call acceptance control, encryption and decryption, conversion to ATM ("Asynchronous Tranfer Mode"), channel assignment, handover and power control.<br><br>		:*The  "Radio Network Controller"  $\rm (RNC)$  is responsible for controlling the base stations.  It is also responsible within the cells for call acceptance control, encryption and decryption, conversion to ATM ("Asynchronous Tranfer Mode"), channel assignment, handover and power control.<br><br>

	⇒   The  "Core Network"  $\rm (CN)$  takes over the switching of the data within the UMTS network.  For this purpose, it contains the following hardware and software components at  "~~Circuit Switching~~" :		⇒   The  "Core Network"  $\rm (CN)$  takes over the switching of the data within the UMTS network.  For this purpose, it contains the following hardware and software components at  "circuit-switching" :
	[[File:EN_Mob_T_3_4_S3.png\|right\|frame\|UMTS access level (with "~~Circuit Switching~~") ''': KORREKTUR'''\|class=fit]]		[[File:EN_Mob_T_3_4_S3.png\|right\|frame\|UMTS access level  $($with  "circuit-switching"$)$ ''': KORREKTUR'''\|class=fit]]
	:*The  "Mobile Switching Center"  $\rm (MSC)$  is responsible for localization and authentication, routing of calls, handover and encryption of user data.<br>		:*The  "Mobile Switching Center"  $\rm (MSC)$  is responsible for localization and authentication, routing of calls, handover and encryption of user data.<br>

Guenter at 14:38, 7 February 2023

2023-02-07T14:38:03Z

← Older revision		Revision as of 16:38, 7 February 2023
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	*The quadrature component is weighted with the square root of the power ratio  $G$  between  $I$  and  $Q$  to compensate power differences.  Then the sum signal  $(I + {\rm j} \cdot Q)$  is multiplied by a complex scrambling code.<br>		*The quadrature component is weighted with the square root of the power ratio  $G$  between  $I$  and  $Q$  to compensate power differences.  Then the sum signal  $(I + {\rm j} \cdot Q)$  is multiplied by a complex scrambling code.<br>

	*Finally the pulse shaping is done with  $g_s(t)$  corresponding to the  [[Digital_Signal_Transmission/Optimierung_der_Basisband%C3%BCbertragungssysteme#Wurzel.E2.80.93Nyquist.E2.80.93Systeme\| $\text{Root Raised Cosine}$]].  Since the ~~reception '''KORREKTUR:~~ receiver~~'''~~ filter is adapted to  $G_s(f)$  the overall frequency response thus fulfills the  [[Digital_Signal_Transmission/Eigenschaften_von_Nyquistsystemen#Erstes_Nyquistkriterium_im_Frequenzbereich\| $\text{first Nyquist criterion}$]].<br><br>		*Finally the pulse shaping is done with  $g_s(t)$  corresponding to the  [[Digital_Signal_Transmission/Optimierung_der_Basisband%C3%BCbertragungssysteme#Wurzel.E2.80.93Nyquist.E2.80.93Systeme\| $\text{Root Raised Cosine}$]].  Since the receiver filter is adapted to  $G_s(f)$  the overall frequency response thus fulfills the  [[Digital_Signal_Transmission/Eigenschaften_von_Nyquistsystemen#Erstes_Nyquistkriterium_im_Frequenzbereich\| $\text{first Nyquist criterion}$]].<br><br>

	Further information on this topic can be found in the section  [[Examples_of_Communication_Systems/Telecommunications_Aspects_of_UMTS#Frequency_responses_and_pulse_shaping_for_UMTS\|		Further information on this topic can be found in the section  [[Examples_of_Communication_Systems/Telecommunications_Aspects_of_UMTS#Frequency_responses_and_pulse_shaping_for_UMTS\|

Guenter at 14:36, 7 February 2023

2023-02-07T14:36:22Z

← Older revision		Revision as of 16:36, 7 February 2023
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	⇒   The  "Core Network"  $\rm (CN)$  takes over the switching of the data within the UMTS network.  For this purpose, it contains the following hardware and software components at  "Circuit Switching" :		⇒   The  "Core Network"  $\rm (CN)$  takes over the switching of the data within the UMTS network.  For this purpose, it contains the following hardware and software components at  "Circuit Switching" :
	[[File:EN_Mob_T_3_4_S3.png\|right\|frame\|UMTS access level (with "Circuit Switching") '''KORREKTUR~~: Netz, Fremdnetz~~'''\|class=fit]]		[[File:EN_Mob_T_3_4_S3.png\|right\|frame\|UMTS access level (with "Circuit Switching") ''': KORREKTUR'''\|class=fit]]
	:*The  "Mobile Switching Center"  $\rm (MSC)$  is responsible for localization and authentication, routing of calls, handover and encryption of user data.<br>		:*The  "Mobile Switching Center"  $\rm (MSC)$  is responsible for localization and authentication, routing of calls, handover and encryption of user data.<br>

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	== CDMA - Multiple access with UMTS ==		== CDMA - Multiple access with UMTS ==
	<br>		<br>
	UMTS uses the multiple access method  [[Modulation_Methods/Direct-Sequence_Spread_Spectrum_Modulation#Block_diagram_and_equivalent_low-pass_model\| $\text{Direct Sequence Code Division Multiple Access}$]]  $\rm (DS–CDMA)$.  The ~~procedure '''KORREKTUR:~~ method~~?'''~~ is sometimes called  "PN–Modulation".<br>		UMTS uses the multiple access method  [[Modulation_Methods/Direct-Sequence_Spread_Spectrum_Modulation#Block_diagram_and_equivalent_low-pass_model\| $\text{Direct Sequence Code Division Multiple Access}$]]  $\rm (DS–CDMA)$.  The method is sometimes called  "PN–Modulation".<br>

	[[File:EN Mob T 3 4 S4.png\|right\|frame\|Principle and signal characteristics with "DS-CDMA" for two users\|class=fit]]		[[File:EN Mob T 3 4 S4.png\|right\|frame\|Principle and signal characteristics with "DS-CDMA" for two users\|class=fit]]

Guenter at 16:14, 6 February 2023

2023-02-06T16:14:04Z

← Older revision		Revision as of 18:14, 6 February 2023
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	⇒   The  "Core Network"  $\rm (CN)$  takes over the switching of the data within the UMTS network.  For this purpose, it contains the following hardware and software components at  "Circuit Switching" :		⇒   The  "Core Network"  $\rm (CN)$  takes over the switching of the data within the UMTS network.  For this purpose, it contains the following hardware and software components at  "Circuit Switching" :
	[[File:~~P ID2209 Mob T 3 4 S3 v1~~.png\|right\|frame\|UMTS access level (with "Circuit Switching") '''KORREKTUR: Netz, Fremdnetz'''\|class=fit]]		[[File:EN_Mob_T_3_4_S3.png\|right\|frame\|UMTS access level (with "Circuit Switching") '''KORREKTUR: Netz, Fremdnetz'''\|class=fit]]
	:*The  "Mobile Switching Center"  $\rm (MSC)$  is responsible for localization and authentication, routing of calls, handover and encryption of user data.<br>		:*The  "Mobile Switching Center"  $\rm (MSC)$  is responsible for localization and authentication, routing of calls, handover and encryption of user data.<br>

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	<br clear =all>		<br clear =all>

	[[File:~~EN_Mob_T_3_4_S5b~~.png\|left\|frame\|Some examples and properties of suitable spreading and scrambling codes\|class=fit]]		[[File:EN_Mob_T_3_4_S5b_v3.png\|left\|frame\|Some examples and properties of suitable spreading and scrambling codes\|class=fit]]
	<br><br><br>		<br><br><br>
	*In the uplink, each mobile station has its own scrambling code and the separation of the individual channels is done using the same code.		*In the uplink, each mobile station has its own scrambling code and the separation of the individual channels is done using the same code.

Guenter at 14:46, 6 February 2023

2023-02-06T14:46:19Z

← Older revision		Revision as of 16:46, 6 February 2023
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	The main motivation for the development of  »'''third generation mobile radio systems'''«   was the realization that 2G systems could not satisfy the bandwidth requirements for the use of multimedia services.		The main motivation for the development of  »'''third generation mobile radio systems'''«   was the realization that 2G systems could not satisfy the bandwidth requirements for the use of multimedia services.

	[[File:~~EN_Mob_T_3_4_S1~~.png\|right\|frame\|Development of the mobile radio systems ~~'''KORREKTUR: Datenrate'''~~\|class=fit]]		[[File:EN_Bei_T_4_1_S1.png\|right\|frame\|Development of the mobile radio systems\|class=fit]]
	The graph shows the development of mobile radio systems from 1995 to 2006 in terms of performance.  The specified data rates were still realistic for 2011 with no more than two active users in one cell.  The maximum values often stated by providers were mostly not reached in practice.		The graph shows the development of mobile radio systems from 1995 to 2006 in terms of performance.  The specified data rates were still realistic for 2011 with no more than two active users in one cell.  The maximum values often stated by providers were mostly not reached in practice.

Hwang at 15:55, 26 January 2023

2023-01-26T15:55:01Z

← Older revision		Revision as of 17:55, 26 January 2023
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	== CDMA - Multiple access with UMTS ==		== CDMA - Multiple access with UMTS ==
	<br>		<br>
	UMTS uses the multiple access method  [[Modulation_Methods/Direct-Sequence_Spread_Spectrum_Modulation#Block_diagram_and_equivalent_low-pass_model\| $\text{Direct Sequence Code Division Multiple Access}$]]  $\rm (DS–CDMA)$.  The procedure is sometimes called  "PN–Modulation".<br>		UMTS uses the multiple access method  [[Modulation_Methods/Direct-Sequence_Spread_Spectrum_Modulation#Block_diagram_and_equivalent_low-pass_model\| $\text{Direct Sequence Code Division Multiple Access}$]]  $\rm (DS–CDMA)$.  The procedure '''KORREKTUR: method?''' is sometimes called  "PN–Modulation".<br>

	[[File:EN Mob T 3 4 S4.png\|right\|frame\|Principle and signal characteristics with "DS-CDMA" for two users\|class=fit]]		[[File:EN Mob T 3 4 S4.png\|right\|frame\|Principle and signal characteristics with "DS-CDMA" for two users\|class=fit]]

Hwang at 15:50, 26 January 2023

2023-01-26T15:50:47Z

← Older revision		Revision as of 17:50, 26 January 2023
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	== CDMA - Multiple access with UMTS ==		== CDMA - Multiple access with UMTS ==
	<br>		<br>
	UMTS uses the multiple access method  [[Modulation_Methods/~~PN%E2%80%93Modulation~~#~~Blockschaltbild_und_.C3.A4quivalentes_Tiefpass.E2.80.93Modell~~\| $\text{Direct Sequence Code Division Multiple Access}$]]  $\rm (DS–CDMA)$.  The procedure is sometimes called  "PN–Modulation".<br>		UMTS uses the multiple access method  [[Modulation_Methods/Direct-Sequence_Spread_Spectrum_Modulation#Block_diagram_and_equivalent_low-pass_model\| $\text{Direct Sequence Code Division Multiple Access}$]]  $\rm (DS–CDMA)$.  The procedure is sometimes called  "PN–Modulation".<br>

	[[File:EN Mob T 3 4 S4.png\|right\|frame\|Principle and signal characteristics with "DS-CDMA" for two users\|class=fit]]		[[File:EN Mob T 3 4 S4.png\|right\|frame\|Principle and signal characteristics with "DS-CDMA" for two users\|class=fit]]

Hwang at 15:48, 26 January 2023

2023-01-26T15:48:08Z

← Older revision		Revision as of 17:48, 26 January 2023
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	⇒   The  "Core Network"  $\rm (CN)$  takes over the switching of the data within the UMTS network.  For this purpose, it contains the following hardware and software components at  "Circuit Switching" :		⇒   The  "Core Network"  $\rm (CN)$  takes over the switching of the data within the UMTS network.  For this purpose, it contains the following hardware and software components at  "Circuit Switching" :
	[[File:P ID2209 Mob T 3 4 S3 v1.png\|right\|frame\|UMTS access level (with "Circuit Switching")\|class=fit]]		[[File:P ID2209 Mob T 3 4 S3 v1.png\|right\|frame\|UMTS access level (with "Circuit Switching") '''KORREKTUR: Netz, Fremdnetz'''\|class=fit]]
	:*The  "Mobile Switching Center"  $\rm (MSC)$  is responsible for localization and authentication, routing of calls, handover and encryption of user data.<br>		:*The  "Mobile Switching Center"  $\rm (MSC)$  is responsible for localization and authentication, routing of calls, handover and encryption of user data.<br>

← Older revision		Revision as of 14:28, 16 March 2026
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	:*The  "Gateway Mobile Switching Center"  $\rm (GMSC)$  organizes the connection to other networks, for example to the landline network.<br>		:*The  "Gateway Mobile Switching Center"  $\rm (GMSC)$  organizes the connection to other networks, for example to the landline network.<br>

	:*Both,  MSC and GMSC,  have access to various databases like  [[Examples_of_Communication_Systems/~~Allgemeine_Beschreibung_von_GSM~~#Switching_and_Management_Subsystem_~~.28SMSS.29~~\| $\text{Home Location Register}$]]  $\rm (HLR)$  and  [[Examples_of_Communication_Systems/~~Allgemeine_Beschreibung_von_GSM~~#Switching_and_Management_Subsystem_~~.28SMSS.29~~\| $\text{Visitor Location Register}$]]  $\rm (VLR)$.<br>		:*Both,  MSC and GMSC,  have access to various databases like  [[Examples_of_Communication_Systems/General_Description_of_GSM#Switching_and_Management_Subsystem_(SMSS)\| $\text{Home Location Register}$]]  $\rm (HLR)$  and  [[Examples_of_Communication_Systems/General_Description_of_GSM#Switching_and_Management_Subsystem_(SMSS)\| $\text{Visitor Location Register}$]]  $\rm (VLR)$.<br>

	The graphic shows the UMTS architecture for circuit switching, where the Core Network  $\rm (CN)$  is organized similarly to the GSM architecture.		The graphic shows the UMTS architecture for circuit switching, where the Core Network  $\rm (CN)$  is organized similarly to the GSM architecture.
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	*Here, the communication partners do not use the channel assigned to them exclusively, but the packets are mixed with those of other users.		*Here, the communication partners do not use the channel assigned to them exclusively, but the packets are mixed with those of other users.
	*One finds there similar components as with the GSM extension  [[Examples_of_Communication_Systems/~~Weiterentwicklungen_des_GSM~~#General_Packet_Radio_Service_~~.28GPRS.29~~\| $\text{General Packet Radio Service}$]]  $\rm (GPRS)$.<br clear=all>		*One finds there similar components as with the GSM extension  [[Examples_of_Communication_Systems/Further_Developments_of_the_GSM#General_Packet_Radio_Service_(GPRS)\| $\text{General Packet Radio Service}$]]  $\rm (GPRS)$.<br clear=all>


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	*The scrambling code  $w(t)$  has the same length and rate as  $c(t)$.<br>		*The scrambling code  $w(t)$  has the same length and rate as  $c(t)$.<br>
	*Due to the scrambling, the codes lose their complete orthogonality; they are called "quasi–othogonal".		*Due to the scrambling, the codes lose their complete orthogonality; they are called "quasi–othogonal".
	* In these codes, the  [[Theory_of_Stochastic_Signals/~~Kreuzkorrelationsfunktion_und_Kreuzleistungsdichte~~#Definition_der_Kreuzkorrelationsfunktion \|$\text{Cross-Correlation Function}$]]  $\rm (CCF)$  between different spreading codes is not equal to zero.		* In these codes, the  [[Theory_of_Stochastic_Signals/Cross-Correlation_Function_and_Cross_Power-Spectral_Density#Definition_der_Kreuzkorrelationsfunktion \|$\text{Cross-Correlation Function}$]]  $\rm (CCF)$  between different spreading codes is not equal to zero.
	*But they are characterized by a distinct  [[Theory_of_Stochastic_Signals/Auto-Correlation_Function_(ACF)\| $\text{ACF value}$]]  around zero, which facilitates detection at the receiver.}}		*But they are characterized by a distinct  [[Theory_of_Stochastic_Signals/Auto-Correlation_Function_(ACF)\| $\text{ACF value}$]]  around zero, which facilitates detection at the receiver.}}

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	*The quadrature component is weighted with the square root of the power ratio  $G$  between  $I$  and  $Q$  to compensate power differences.  Then the sum signal  $(I + {\rm j} \cdot Q)$  is multiplied by a complex scrambling code.<br>		*The quadrature component is weighted with the square root of the power ratio  $G$  between  $I$  and  $Q$  to compensate power differences.  Then the sum signal  $(I + {\rm j} \cdot Q)$  is multiplied by a complex scrambling code.<br>

	*Finally the pulse shaping is done with  $g_s(t)$  corresponding to the  [[Digital_Signal_Transmission/Optimierung_der_Basisband%C3%BCbertragungssysteme#Wurzel.E2.80.93Nyquist.E2.80.93Systeme\| $\text{Root Raised Cosine}$]].  Since the receiver filter is adapted to  $G_s(f)$  the overall frequency response thus fulfills the  [[Digital_Signal_Transmission/~~Eigenschaften_von_Nyquistsystemen~~#~~Erstes_Nyquistkriterium_im_Frequenzbereich~~\| $\text{first Nyquist criterion}$]].<br><br>		*Finally the pulse shaping is done with  $g_s(t)$  corresponding to the  [[Digital_Signal_Transmission/Optimierung_der_Basisband%C3%BCbertragungssysteme#Wurzel.E2.80.93Nyquist.E2.80.93Systeme\| $\text{Root Raised Cosine}$]].  Since the receiver filter is adapted to  $G_s(f)$  the overall frequency response thus fulfills the  [[Digital_Signal_Transmission/Properties_of_Nyquist_Systems#First_Nyquist_criterion_in_the_frequency_domain\| $\text{first Nyquist criterion}$]].<br><br>

	Further information on this topic can be found in the section  [[Examples_of_Communication_Systems/Telecommunications_Aspects_of_UMTS#Frequency_responses_and_pulse_shaping_for_UMTS\|		Further information on this topic can be found in the section  [[Examples_of_Communication_Systems/Telecommunications_Aspects_of_UMTS#Frequency_responses_and_pulse_shaping_for_UMTS\|
	"Frequency responses and pulse shaping for UMTS"]]  of the book "Examples of communication systems".  There you will also find a graphic with the Nyquist frequency response  $H(f)$.  It is a  [[Linear_and_Time_Invariant_Systems/~~Einige_systemtheoretische_Tiefpassfunktionen~~#~~Cosinus~~-~~Rolloff~~-~~Tiefpass~~\|$\text{Raised Cosine}$]] with the following dimensioning:		"Frequency responses and pulse shaping for UMTS"]]  of the book "Examples of communication systems".  There you will also find a graphic with the Nyquist frequency response  $H(f)$.  It is a  [[Linear_and_Time_Invariant_Systems/Some_Low-Pass_Functions_in_Systems_Theory#Raised-cosine_low-pass_filter\|$\text{Raised Cosine}$]] with the following dimensioning:
	*The UMTS chip rate is  $R_{\rm C} = 3.84 \ \rm Mbit/s$.  The center of the slope must be at  $f_{\rm N} =R_{\rm C}/2 = 1.92 \ \rm MHz$  to avoid intersymbol interference   ⇒   $H(f = \pm f_{\rm N}) = 0.5$.		*The UMTS chip rate is  $R_{\rm C} = 3.84 \ \rm Mbit/s$.  The center of the slope must be at  $f_{\rm N} =R_{\rm C}/2 = 1.92 \ \rm MHz$  to avoid intersymbol interference   ⇒   $H(f = \pm f_{\rm N}) = 0.5$.

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	<br>		<br>
	In order to meet the ever-increasing demand for higher data rates in mobile communications, the UMTS standard has been continuously developed.  The most important changes within the third generation resulted from the introduction of		In order to meet the ever-increasing demand for higher data rates in mobile communications, the UMTS standard has been continuously developed.  The most important changes within the third generation resulted from the introduction of
	*[[Examples_of_Communication_Systems/~~Weiterentwicklungen_von_UMTS~~#~~High.E2.80.93Speed_Downlink_Packet_Access~~\| $\text{High Speed Downlink Packet Access}$]]  $\rm (HSDPA)$  (Release 5, 2002, market launch 2006) and <br>		*[[Examples_of_Communication_Systems/Further_Developments_of_UMTS#High–Speed_Downlink_Packet_Access\| $\text{High Speed Downlink Packet Access}$]]  $\rm (HSDPA)$  (Release 5, 2002, market launch 2006) and <br>

	*[[Examples_of_Communication_Systems/~~Weiterentwicklungen_von_UMTS~~#~~High.E2.80.93Speed_Uplink_Packet_Access~~\| $\text{High Speed Uplink Packet Access}$]]  $\rm (HSUPA)$  (Release 6, 2005, market launch 2007).<br><br>		*[[Examples_of_Communication_Systems/Further_Developments_of_UMTS#High–Speed_Uplink_Packet_Access\| $\text{High Speed Uplink Packet Access}$]]  $\rm (HSUPA)$  (Release 6, 2005, market launch 2007).<br><br>

	Together, HSDPA and HSDUPA result in the  $\rm HSPA$ standard.<br>		Together, HSDPA and HSDUPA result in the  $\rm HSPA$ standard.<br>
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	These increases were achieved by		These increases were achieved by
	*the introduction of additional  [[Examples_of_Communication_Systems/~~Weiterentwicklungen_von_UMTS~~#Zus.C3.A4tzliche_Kan.C3.A4le_in_HSDPA \| $\text{shared channels}$]]  (for example  $\rm HS\hspace{0.05cm}–\hspace{-0.05cm}DSCH$),<br>		*the introduction of additional  [[Examples_of_Communication_Systems/Further_Developments_of_UMTS#Zus.C3.A4tzliche_Kan.C3.A4le_in_HSDPA \| $\text{shared channels}$]]  (for example  $\rm HS\hspace{0.05cm}–\hspace{-0.05cm}DSCH$),<br>

	*the  [[Examples_of_Communication_Systems/Further_Developments_of_UMTS#HARQ_procedure_and_.22Node_B_Scheduling.22\| $\text{Hybrid–ARQ Procedure}$]]  $\rm (HARQ)$  and  "Node B scheduling",<br>		*the  [[Examples_of_Communication_Systems/Further_Developments_of_UMTS#HARQ_procedure_and_.22Node_B_Scheduling.22\| $\text{Hybrid–ARQ Procedure}$]]  $\rm (HARQ)$  and  "Node B scheduling",<br>
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	{{Display}}		{{Display}}
			[[de:Mobile_Kommunikation/Die_Charakteristika_von_UMTS]]