Interview Questions.

Question 1. Tell Me How Does Soft/softer Handover Work?

Answer :

? Soft/softer handover down-link: UE rake receiver performs most ratio combining, i.E. UE combines multi-direction alerts and shape a stronger signal. 

? Soft handover up-hyperlink: RNC plays selection combining, i.E. RNC selects the higher sign coming from multiple NodeB.

? Softer handover up-hyperlink: NodeB performs most ratio combining, i.E. NodeB rake receiver combines signals from one-of-a-kind paths and bureaucracy a stronger signal

Question 2. What Is Pole Capacity?

Answer :

The uplink noise will increase with the loading exponentially. When the up-link noise strategies infinity then no more users may be brought to a cell - and the cell loading is near one hundred% and has reached its pole potential

Wireless Interview Questions
Question 3. Explain Sir?

Answer :

SIR is the Signal-to-Interference Ratio - the ratio of the power in committed physical control channel bits to the strength density of interference and noise after dispreading.

Question four. Rscp Stands For?

Answer :

RSCP stands for Received Signal Code Power - the strength per chip in CPICH averaged over 512 chips.

UMTS Tutorial
Question 5. Do You Know How Does Tma Work?

Answer :

A TMA reduces gadget noise, improves up-link sensitivity and results in longer UE battery existence. Sensitivity is the minimal enter electricity needed to get a appropriate signal-to-noise ratio (SNR) on the output of the receiver. It is determined by using receiver noise figure, thermo noise energy and required SNR. Thermo noise power is determined by bandwidth and temperature, SNR is decided via modulation method, therefore the simplest variable is noise determine.

UMTS Interview Questions
Question 6. Explain Typical Maximum Path Loss?

Answer :

The most direction loss is depending on the service and supplier hints; usually it's miles in between a hundred thirty five to 140dB for city areas and among a hundred and fifty to 160dB for rural areas.

Question 7. Do You Know What Is A Typical Antenna Gain?

Answer :

The antenna benefit depends on antenna model; in hyperlink price range we use around 17dBi.

4G Interview Questions
Question 8. Tell Me What Is A Typical Nodeb Maximum Output Power?

Answer :

The maximum NodeB output strength is typically 20W or 40W, this is, 43dBm or 46dBm.

Question nine. What Is A Typical Nodeb Sensitivity Level?

Answer :

The carrier and cargo determines the NodeB sensitivity; in preferred, in a no-load circumstance, the sensitivity is between -115dBm to -125dBm.

For Ericsson, the NodeB sensitivity degree is calculated at around: 

CS12.2: -124 dBm ,PS-64: -119 dBm, PS-128: -a hundred and fifteen dBm, PS-384: -115 dBm

Wideband Code Division Multiple Access (WCDMA) Interview Questions
Question 10. Explain Several Event In 3g?

Answer :

? Event 1A:UTRAN will add the new cellular in the UE's energetic mobile listing and could send an ACTIVE SET UPDATE message. 

? Event 1B:UTRAN will send ACTIVE SET UPDATE message to get rid of the mobile from UE's lively set. 

? Event 1C:UTRAN will send ACTIVE SET UPDATE message so as to get rid of one or extra cells and will add one or more cells. The simplest restriction for 1C is that there must be atleast one radio hyperlink that is not suffering from the method.

Question eleven. Tell Me What Is Typical Tma Gain?

Answer :

TMA typically has a 12 dB benefit; but, the effective benefit comes from noise parent discount and the benefit is near or equivalent to the feeder loss.

Question 12. What Is Soft Handover?

Answer :

Soft handover means that the radio links are introduced and removed in a way that the UE always continues as a minimum one radio link to the UTRAN. Soft handover is performed by macro range, which refers to the condition that several radio hyperlinks are active at the same time. Normally gentle handover can be used when cells operated at the equal frequency are modified.

Wireless Interview Questions
Question 13. What Is Hard Handover?

Answer :

Hard handover way that every one the antique radio links inside the UE are eliminated earlier than the brand new radio hyperlinks are hooked up. Hard handover can be seamless or non-seamless. Seamless tough handover approach that the handover isn't always perceptible to the person. In practice a handover that requires a change of the provider frequency (inter-frequency handover) is constantly performed as hard handover.

Question 14. What Are The Types Of Hand Over?

Answer :

? Hard Handover
? Soft Handover

Question 15. Explain Iden(incorporated Digital Enhanced Network)?

Answer :

A wireless era for Motorola
It has the talents of digi-cellular telephone, 2 way radio, alphanumeric pager and records modem / fax modem in a unmarried network
Operational bands are 800 MHz, 900 MHz and 1.5 GHz
iDEN is based on TDMA(Time Division Multiple Access) and GSM structure
For voice compression it uses Motorola's Vector Sum Excited Linear Predictors vocoder
For turning in sixty four KBPS over a 25 KHz channel, it uses QAM modulation.
IDEN is designed to serve the mobile user for gaining access to statistics fast with out carrying numerous devices.
Question sixteen. What Is Hlr (domestic Location Register)?

Answer :

For GSM and CDMA wi-fi networks
It's responsibility is to authenticate and authorize subscribers and their services.
Question 17. Explain Gprs (fashionable Packet Radio Service)?

Answer :

Packet oriented cell facts service to be had to the customers of 2G cellular systems.
It is international device for speaking through cellular telephones using GSM in addition to in 3G structures.
GPRS facts transfer is charged in line with MB of traffic transferred, where as in circuit switching, information transfer is charged per minute of connection time
GPRS is higher packet switching provider, as opposed to circuit switching.
2G cellular systems are mixed with GPRS and called 2.5 G.
Provides slight velocity records transfer through using unused TDMA channels, which include GSM.
Question 18. Explain Gsm (global System For Mobile Communications)?

Answer :

Most popular widespread for cellular telephony structures, originated from Group Special Mobile
The ubiquity of GSM enables the worldwide roaming arrangements among cellular cellphone operators.
Both signaling and speech channels are virtual, and as a consequence GSM is considered as 2G mobile cellphone device.
GSM popular benefited customers the capacity to roam and switch companies with out replacing the hand sets and network operators.
GSM implements low-fee implementation of Short Message Service
UMTS Interview Questions
Question 19. Can You Please Explain The Difference Between 3g And 2g?

Answer :

Packet information velocity is higher in 3G, and it's miles as much as 384 KBPS
Voice and sms speed is also 384 KBPS in 3G
2G utilizes special switching strategies for voice and facts, wherein as 3G uses single switching, regardless of data
3G has as a minimum 2MB of facts link of a cell, where in 2G the statistics price is in KBPS
3G has WiMAX facility for quicker VOIP and net
2G makes use of GSM TDMA technology with narrow band 2 hundred KHz.
3G uses CD-MA era with broadband five MHz, with identical frequency provider and time.
Question 20. Explain The Disadvantages Of 3g?

Answer :

The cost of cellular infrastructure , upgrading base stations is very excessive
Needs distinctive handsets.
Roaming and records/voice work collectively has no longer but been applied
Power consumption is excessive
Requires nearer base stations and are expensive
Spectrum-license charges, network deployment costs and handset subsidies subscribers are notable.
Question 21. Explain The Advantages Of 3g?

Answer :

Overcrowding is relieved in present systems with radio spectrum
Bandwidth, security and reliability are extra
Provides interoperability among provider providers
Availability of fixed and variable fees
Support to devices with backward compatibility with present networks
Always on line gadgets - 3G makes use of IP connectivity which is packet based
Rich multi media offerings are available
Question 22. What Is Evolution-information Optimized?

Answer :

Evolution-Data Optimized or Evolution-Data only, abbreviated as EV-DO or EVDO and frequently EV, is a telecommunications wellknown for the wireless transmission of facts via radio indicators, generally for broadband Internet access. It makes use of multiplexing strategies which includes code department multiple get right of entry to (CDMA) as well as time department a couple of access (TDMA) to maximize both man or woman user's throughput and the overall machine throughput. It is standardized by way of third Generation Partnership Project 2 (3GPP2) as part of the CDMA2000 family of requirements.

Question 23. What Is 3gpp Long Term Evolution?

Answer :

LTE (Long Term Evolution) is the trademarked mission name of a high overall performance air interface for cell cellular telephony. It is a challenge of the third Generation Partnership Project (3GPP), operating beneath a named trademarked by way of one of the associations inside the partnership, the European Telecommunications Standards Institute.

Question 24. Explain High Speed Packet Access?

Answer :

High Speed Packet Access (HSPA) is a collection of  cell telephony protocols, High Speed Downlink Packet Access (HSDPA) and High Speed Uplink Packet Access (HSUPA), that extends and improves the overall performance of current WCDMA protocols. A in addition fashionable, Evolved HSPA (also known as HSPA+), turned into released overdue in 2008 with subsequent adoption international into 2010.

4G Interview Questions
Question 25. Explain Enhanced Data Rates For Gsm Evolution?

Answer :

Enhanced Data charges for GSM Evolution (EDGE) (also known as Enhanced GPRS (EGPRS), or IMT Single Carrier (IMT-SC), or Enhanced Data costs for Global Evolution) is a backward-like minded digital mobile smartphone generation that permits stepped forward information transmission fees, as an extension on top of preferred GSM. EDGE is taken into consideration a 3G radio era and is a part of ITU's 3G definition.

Question 26. Explain Wimax?

Answer :

WiMAX, an acronym for Worldwide Interoperability for Microwave Access, is a telecommunications protocol that gives constant and completely mobile net get entry to. The present day WiMAX revision offers as much as forty Mbps with the IEEE 802.16m update anticipated provide up to at least one Gbit/s fixed speeds. (WiMAX is based totally on the IEEE 802.Sixteen popular, additionally called Broadband Wireless Access). The call WiMAX changed into created by way of the WiMAX Forum, which was fashioned in June 2001 to promote conformity and interoperability of the standard.

Question 27. Explain Digital Enhanced Cordless Telecommunications?

Answer :

Digital Enhanced Cordless Telecommunications (DECT), known as Digital European Cordless Telephone until 1995, is an ETSI fashionable for digital transportable phones (cordless home phones), usually used for domestic or company purposes. It is acknowledged via the ITU as fulfilling the IMT-2000 requirements and thus qualifies as a 3G machine. Within the IMT-2000 organization of technology, DECT is referred to as IMT-2000 Frequency Time (IMT-FT)

Wideband Code Division Multiple Access (WCDMA) Interview Questions
Question 28. Explain Cdma2000?

Answer :

CDMA2000 (additionally referred to as IMT Multi?Carrier (IMT?MC)) is a circle of relatives of 3G cell generation standards, which use CDMA channel access, to send voice, records, and signaling records among mobile telephones and cellular web sites. The set of requirements consists of: CDMA2000 1X, CDMA2000 EV-DO Rev. 0, CDMA2000 EV-DO Rev. A, and CDMA2000 EV-DO Rev. B. All are approved radio interfaces for the ITU's IMT-2000.

Question 29. What Is 4g?

Answer :

4G refers to the fourth generation of mobile wireless requirements. It is a successor to 3G and 2G standards. The nomenclature of the generations typically refers to a exchange inside the fundamental nature of the provider. The first was the move from analogue (1G) to digital (2G) transmission. This turned into accompanied by way of multi-media aid, spread spectrum transmission and at the least 200 kbit/s (3G) and now 4G, which refers to all IP packet-switched networks, mobile extremely-broadband (gigabit velocity) access and multi-carrier transmission.

Question 30. What Is 2g?

Answer :

2G (or 2-G) is short for 2nd-technology wireless smartphone era. Second technology 2G cell telecom networks were commercially released on the GSM standard in Finland in 1991. Three number one advantages of 2G networks over their predecessors were that cellphone conversations had been digitally encrypted, 2G structures have been significantly more green on the spectrum bearing in mind far extra cell smartphone penetration tiers; and 2G added records services for cellular, beginning with SMS text messages.

Question 31. What Is Universal Mobile Telecommunications System?

Answer :

Universal Mobile Telecommunications System (UMTS) is one of the third-generation (3G) mobile telecommunications technologies, which is likewise being evolved right into a 4G generation. The first deployment of the UMTS is the release99 (R99) architecture. It is precise by way of 3GPP and is a part of the global ITU IMT-2000 standard.

Question 32. What Is International Telecommunication Union?

Answer :

The International Telecommunication Union is the eldest business enterprise within the UN circle of relatives still in existence. It changed into founded because the International Telegraph Union in Paris on 17 May 1865 and is today the main United Nations employer for records and conversation generation troubles, and the global focal factor for governments and the personal quarter in developing networks and offerings.

Question 33. Explain 3g?

Answer :

Third era (3G) wi-fi networks will offer quicker data transfer quotes than modern-day networks. The first era of wireless (1G) was analog mobile. The second generation (2G) is digital cellular, proposing included voice and records communications. So-referred to as 2.5G networks 

provide incremental pace increases. 3G networks will provide dramatically advanced records switch fees, enabling new wireless applications which include streaming media.