What is CDMA and its architecture?
The architecture of the CDMA mobile sys tem (CMS) is developed based on three func tion groups service resource, service control, and service management groups. In this pa per, the CMS architecture is discussed from the point of view of implementing these func tions. The softer handoff is implemented in one card.
Which are the components of CDMA architecture?
CDMA Network Structure
- CDMA2000 1x Network Elements: CDMA network architecture consists of following elements.
- Mobile Station (MS):
- Base Transceiver Station (BTS):
- Base Station Controller (BSC):
- Packet Control Function (PCF):
- Packet Data Service Node (PDSN):
- Home Agent (HA):
- Visitor Location Register (VLR):
Is-95 a CDMA architecture?
The proprietary name for IS-95 is cdmaOne. It is a 2G mobile telecommunications standard that uses code-division multiple access (CDMA), a multiple access scheme for digital radio, to send voice, data and signaling data (such as a dialed telephone number) between mobile telephones and cell sites.
What is MSC function in CDMA architecture?
The mobile switching center (MSC) is the primary service delivery node for GSM/CDMA, responsible for routing voice calls and SMS as well as other services (such as conference calls, FAX, and circuit-switched data).
What are the types of CDMA?
In general, CDMA belongs to two basic categories: synchronous (orthogonal codes) and asynchronous (pseudorandom codes).
IS-95 and is 136?
Difference between IS-136 and IS-95 IS-136 uses TDMA multiple access, while IS-95 uses CDMA multiple access techniques. IS-136 channel bandwidth is about 30 KHz and IS-95 channel bandwidth is about 1250 KHz. IS-136 uses pi/4(DQPSK) and IS-95 uses QPSK modulation techniques in physical layer.
How BSC and MSC are connected?
The BSC is the connection between the mobile and the MSC. The BSC also translates the 13 Kbps voice channel used over the radio link to the standard 64 Kbps channel used by the Public Switched Telephone Network (PSDN) or ISDN. It assigns and releases frequencies and time slots for the MS.
What is code division multiple access ( CDMA ) technology?
CDMA – Technology. Code Division Multiple Access (CDMA) is a sort of multiplexing that facilitates various signals to occupy a single transmission channel. It optimizes the use of available bandwidth.
How many code channels are in a CDMA band?
Centralized Methods The band used in CDMA is 824 MHz to 894 MHz (50 MHz + 20 MHz separation). Frequency channel is divided into code channels. 1.25 MHz of FDMA channel is divided into 64 code channels.
What are the advantages and disadvantages of CDMA?
It has the following advantages − CDMA requires a tight power control, as it suffers from near-far effect. In other words, a user near the base station transmitting with the same power will drown the signal latter. All signals must have more or less equal power at the receiver Rake receivers can be used to improve signal reception.
Which is true of the reuse efficiency of CDMA?
Hence, CDMA has 100% frequency reuse. Use of same frequency in surrounding cells causes some additional interference. In CDMA frequency, reuse efficiency is 0.67 (70% eff.) = -1.73dB CDMA has a soft capacity. The greater the number of codes, the more the number of users.