IS-95

Question 1

Which multiple access technique does IS-95? Is it digital or analog system? Is this technique it for data, voice or both?

Answer 1

CDMA. Digital. For data.

Question 2

What is spectrum of IS-95? How much does every carrier/user uses? How much is gaurd bandwidth? Are they taken from users bandwidth?

Answer 2

From 1.25 to 5 MHz. 1.25 MHz. 0.02 MHz. Yes.

Question 3

Give examples of 3G systems which use CDMA?

Answer 3

Wideband systems: WCDMA or wideband CDMA and UMTS or universal mobile telecommunications system which uses WCDMA.

Question 4

Which channel does MS use to scan for BS? How does it announce itself and gain access? Which channel does it use to listen for pages?

Answer 4

Forward channel. It sends encrypted pass key. Forward channel.

Question 5

What are maximum vocoders rates for IS-95?

Answer 5

From 1200 bps to 9600 bps.

Question 6

What is rake reciever?

Answer 6

Device to encounter multipath fading effect by gathering it from different paths. It combines signal more than one chip interval apart.

Question 7

What type of hand off does IS-95 use?

Answer 7

Soft handoff.

Question 8

What is name of sparators and integrator in rake reciever?

Answer 8

Correlators. Syncronizaion adder.