Some GSM, UMTS and LTE Measurement Units

GSM
Here, the world is still quite simple. Once the mobile has found a cell it keeps monitoring it's received signal power and computes the Received Signal Strength Indicator (RSSI) over the complete carrier frequency (200 kHz). Neighboring cells use different frequencies and the same value is calculated for those as well.
UMTS
Here, things get a bit more complicated as all cells use the same frequency. As a result not only the received signal strength is important but also the noise level generated by neighboring cells. In the end, what good does it do to you when the signal level is strong but most of it is interference? That's why there are three values:

• RSCP: The Received Signal Code Power: That's the power level the pilot channel of a cell is received with and usually expressed in dBm (mW on a logarithmic scale).

• RSSI: In UMTS that's the signal power over the complete 5 MHz carrier which includes all components received, including the signals from neighboring cells on the same frequency.

• EcNo: (Signal to Noise ratio): That's the received energy per chip (Ec) of the pilot channel divided by the total noise power density (No). In other words the EcNo is the RSCP divided by the RSSI. And again in other words: The better this value the better the signal can be distinguished from the noise and the faster the data transmission will be. The EcNo is usually expressed in dB as it's a relative value. The value is negative as the RSCP is smaller than the total received power.

LTE
LTE networks also use the same carrier frequency in neighboring cells so again the signal level and interference are important:

• RSRP: That's the Received Power of the Reference Signal.

• RSSI: That's the total received power including Interference from neighboring cells and other sources.

• RSRQ: That's the Reference Signal Received Quality and equals the RSRP divided by the RSSI. As above the better this value, the better can the signal of the cell be received against the interference generated by other cells. It's kind of the EcNo of LTE...

Quite a lot of similarities between UMTS and LTE from a high level point of view even though the values are measured in quite a different way due to the different air interface natures (WCDMA vs. OFDMA).

source:internet

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Understanding UMTS- Evolutionary Strategies

Understanding UMTS- Evolutionary Strategies pdf

Release ’99 of the 3GPP specifications for UMTS are sufficient for operators to begin
to plan and deploy UMTS networks which consist of the brand new W-CDMA, FDDmode
air interface added to the standardised GSM Phase 2+ and GPRS core network. However the further evolution of UMTS will be strongly dependant on future standardisation work, in both 3GPP and in other relevant groups.
The speed of development and the eventual implementation of future specifications will also be immensely dependent on market demands and conditions, since these will determine the support and resources for such development.
Amongst the key broad areas in which ongoing specification and standardisation work is likely to impact the future of UMTS, are the following :
1. Upgrades to the core network, in particular beginning the move towards unifying and integrating the packet and circuit-switched domains, and providing the basis for multimedia services, on the basis of IP transport protocols.
2. Further development of service-related architectures, interfaces and procedures, including the continued evolution of CAMEL, USIM, security and fraud protection and the Open Services Architecture.
3. Further specification of the TDD mode of operation at the UMTS air interface. Since TDD spectrum is currently not applicable in Japan, TDD mode is not a priority for Japanese infrastructure and terminal vendors in the short term.
4. Investigation of possible commonalities and harmonisation of UMTS work in 3GPP with cdma2000 development in progress by 3GPP2. This is in line with the ITU concept of a family of 3G standards able to seamlessly interoperate easily. Other important and ongoing harmonisation efforts also include those between the GSM and US TDMA communities.
5. Although not strictly part of “UMTS”, specification of GERAN (GSM/EDGE Radio Access Network) is a development process which now falls under the auspices of 3GPP. EDGE is by no means certain of wide market acceptance and is not a requirement in implementing UMTS.
Although there is a body of opinion which supports the use of EDGE as a technology
to fill the coverage gaps between initial islands of UMTS, the existence of EDGE capable
handsets and complete GERAN specifications from 3GPP will lag behind the introduction of UMTS, and the first UMTS networks will therefore almost certainly still use GSM alone as the fill-in radio access technology.

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WCDMA (UMTS) DEPLOYMENT HANDBOOK-Planning and Optimization Aspects

http://www.4shared.com/file/11298595...tsSep2006.html

In this book, using the experience we have gained from performing many network
assessments, we focus on the day-to-day tasks and real world choices that confront operators.
We have chosen to minimize paraphrasing of the standard. This is not to say that we
disregard the ample documentation written by the Third Generation Partnership Project
(3GPP), also known as the standard. We do refer to the standard throughout this book
but rather than present its concepts in a dry manner, we introduce only the sections that
readers can use to deepen their knowledge on specific topics. We selected these topics to
help network planners and optimization engineers make a better transition from GSM to
WCDMA while understanding how to perform the required tasks.

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