Explanation: Mobile communication is use of technology that allows users to communicate from different locations without the use of physical medium (wires or cables).

Explanation: Examples of different types of wireless communication devices are mobiles, Zigbee wireless technology, Cordless telephones, GPS, satellite television, Wi-Fi, and wireless computer parts.

Explanation: Wireless communications have enabled billions of people to connect to the Internet, allowing them to profit from today’s digital economy. It also allows for economies of scale by lowering the cost of network infrastructure and user devices, making services more inexpensive.

Explanation: Spatial multiplexing is a transmission method used in MIMO wireless communications to transmit encoded data signals independently and separately (so-called streams) from each of the multiple transmit antennas.

Explanation: Space diversity is also known as antenna diversity. It is one of the popular forms of diversity used in wireless communications. Signals received from the spatially separated antenna on the mobile would have essentially uncorrelated envelopes for antenna separation.

Explanation: Since the initial development in the year 1990, MIMO Wireless Communications have become integral part of the most forthcoming commercial and next generation wireless data communication systems.

Explanation: MIMO is one of several forms of smart antenna technology, the others being MISO (multiple input, single output) and SIMO (single input, multiple output). It is an antenna technology for wireless communications in which multiple antennas are used at both the source and the destination.

Explanation: Simulcast is a reliable technique used by paging system by transmitting the same paging signal from multiple paging transmitters at approximately equal times.

Explanation: Cordless telephone systems are wireless, but they have a disadvantage of limited coverage area with cell size of approx. 300 m. Being digital, they have very less chance of eaves dropping.

Explanation: FCC (Forward Control Channel) and RCC (Reverse Control Channel) are control channels responsible for initiating mobile calls.

Explanation: Interim Standard 95 (IS-95) is the most popular CDMA standard of second generation networks. IS-136 is a TDMA standard of 2G. EDGE is a standard of 2.5G and ETACS is a 1G standard.

Explanation: GSM (Global System for Mobile) is a TDMA standard for 2G network. HSCSD (High Speed Circuit Switched Data), GPRS (General Packet Radio Service) and EDGE (Enhanced Data rates for GSM Evolution) are TDMA standards of 2.5G technology.

Explanation: The 3G evolution for GSM, IS-136 and PDC systems leads to W-CDMA (Wideband CDMA). It is based on the network fundamentals of GSM, as well as merged versions of GSM and IS-136 through EDGE. GPRS, EDGE and HSCSD are 2.5G networks.

Explanation: 3G Cdma2000 is based on the original IS-95 and IS-95A CDMA standards, as well as the 2.5G IS-95B air interface. While upgrading, Cdma2000 maintains backward compatibility with existing IS-95, IS-95A and IS-95B equipments. Thus, Cdma2000 allow wireless carriers to introduce a family of new high data rate Internet access capabilities within existing systems.

Explanation: IEEE 802.11 is a set of media access control and physical layer specification for implementing WLAN computer communication. It was founded in 1987 to begin standardization of spread spectrum WLANs for use in the ISM bands.

Explanation: Bluetooth uses GFSK (Gaussian Frequency Shift Keying). When GFSK is used for Bluetooth modulation, the frequency of the carrier is shifted to carry the modulation. By doing this the Bluetooth modulation achieves a bandwidth of 1 MHz with stringent filter requirements to prevent interference on other channels.

Explanation: Hexagonal cell shape is a simplistic model of radio coverage for each base station. It has been universally adopted since the hexagon permits easy and manageable analysis of a cellular system.

Explanation: Locator receiver is a spare receiver in each base station. It is used to scan and determine signal strengths of mobile users which are in neighbouring cells.