CDMA for cellular systems can be described as follows.As with FDMA，each cell is allocated a frequency（ ），which is split into two parts,half for reverse（mobile unit to base station）and half for（ ）（base station to mobile unit）.For full-duplex（ ）.a mobile unit uses both reverse and forwardchannels.Transmission is in the form of direct-sequence spread（ ）,which uses a chipping code to increase the data rate of the transmission,resulting inan increased signal bandwidth.Multiple access is provided by assigning（本题）chipping codes to multiple users,so that the receiver can recover the transmission of an individual unit from multiple transmissions.A.concurrentB.orthogonalC.higherD.lower
CDMA for cellular systems can be described as follows.As with FDMA，each cell is allocated a frequency（ ），which is split into two parts,half for reverse（mobile unit to base station）and half for（ ）（base station to mobile unit）.For full-duplex（ ）.a mobile unit uses both reverse and forwardchannels.Transmission is in the form of direct-sequence spread（ ）,which uses a chipping code to increase the data rate of the transmission,resulting inan increased signal bandwidth.Multiple access is provided by assigning（本题）chipping codes to multiple users,so that the receiver can recover the transmission of an individual unit from multiple transmissions.
A.concurrent
B.orthogonal
C.higher
D.lower
B.orthogonal
C.higher
D.lower
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● (74) is a contiguous，numbered set of variables of a given base type，which can be used and passed to functions as a unit.(74) A．RecordB．ArrayC．ParameterD．File
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Bluetooth is a universal radio interface in the(71)frequency hand that enables portable electronic devices to connect and communicate wirelessly via short-range, ad hoc networks. Each unit can simultaneously communicate with up to(72)other units per piconet. Moreover, each unit can simultaneously(73)to several piconets. Eliminates the need for wires, cables and connectors for and between cordless or mobile phones, modems, headsets, PDAs, Computers, printers, projectors, local area networks, and so on, and paves the way for new and completely different devices and applications. Technology Characteristics(74)symbol rate exploits maximum available(75)bandwidth。A．1.95GHzB．2.45GHzC．4.45GHzD．11.45GHz
CDMA for cellular system can be described as follows. As with FDMA, each cell is allocated a frequency （71） , when is split into two parts, half for reverse (mobile unit to base station) and half for （72） (base station to mobile unit). For full-duplex （73） , a mobile unit both reverse and forward channels. Transmission is in the form. of direct-sequence spread （74） , which used a chipping code to increase the data rate of the transmission, resulting is an increased signal bandwidth. Multiple access is provided by assigning （75） chipping codes to multiple users, so that the receiver can recover the transmission of an individual unit from multiple transmissions.A.wareB.signalC.bandwidthD.domain
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( ) is a contiguous, numbered set of variables of a given base type, which can be used and passed to functions as a unit.A.RecordB.ArrayC.ParameterD.File
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