Determine downink of a cdma system, Electrical Engineering

Consider the point-to-point radio link introduced in problem 9. By how much must transmit power be increased to maintain the maximum BER of 10-5 if the channel is flat Rayleigh-fading:

(a) When coherently detected BPSK and FSK, and DPSK and noncoherent FSK used?

(b) What is the required increase in transmit power if the channel is Rician with Kr = 10 and DPSK is used? What are the expected results for Kr → 0?

Consider a mobile radio link with a carrier frequency of fc = 1,200 MHz, a bit rate of 3 kbits/s, and a required maximum BER of 10-4
. The modulation format is MSK with differential detection. A maximum transmit power of 10 dBm (EIRP) is used with 5-dB gain antennas and RXs with noise figures of 9 dB.

(a) Assuming that the channel is flat-Rayleigh-fading and that BS and MS heights are 40 and 3m, respectively, what is the achievable cell radius in a suburban environment according to the Okumura-Hata path loss model?

(b) Assume that the channel is frequency-dispersive Rayleigh fading and characterised by a classical Jakes' Doppler spectrum. What is the maximum mobile terminal speed for an irreducible BER due to frequency dispersion of 10-5?

To illustrate the impact of diversity, we look at the average BER for BPSK and MRC, given approximately by Eq. (13.35). Assume that the average SNR is 20 dB.

(a) Calculate the average BER for Nr = 1 receive antennas.

(b) Calculate the average BER for Nr = 1 receive antennas.

(c) Calculate the SNR that would be required in a one-antenna system in order to achieve the same BER as a three-antenna system at 20 dB.

TDMA requires a temporal guard interval.

(a) The cell radius of a mobile system is specified as 3,000 m and the longest impulse response in the cell is measured as 10 μs. What is the minimum temporal guard interval needed to avoid overlapping transmissions?

(b) How is the temporal guard interval reduced in GSM?

Consider a CDMA system with a target SINR of 6 dB. At the cell boundary, the SNR is 9 dB. The spreading factor is 64; the orthogonality factor is 0.4. How many users can be served per cell (disregard adjacent cell interference).

Consider the downink of a CDMA system with 4 Mchips/s chip rate. The cell contains 4 data users, with (coded) data rates of 500, 500, 25, and 125 kbit/s. How many speech users (with coded data rate of 15.6 kbit/s can be served, assuming that downlink spreading  codes should be completely orthogonal?

Posted Date: 2/27/2013 1:25:09 AM | Location : United States

Related Discussions:- Determine downink of a cdma system, Assignment Help, Ask Question on Determine downink of a cdma system, Get Answer, Expert's Help, Determine downink of a cdma system Discussions

Write discussion on Determine downink of a cdma system
Your posts are moderated
Related Questions
What are loosely coupled systems? In loosely coupled systems every CPU may have its own bus control logic. The bus arbitration is handled by an external circuit, common to all

Q. (a) Consider the capacitor - input filter circuit of Figure and obtain the z-parameters for the circuit. (b) Determine the transfer function V 2 /V 1 when I 2 is zero.

list the key parameters to describe the ideal operational amplifier

List the operation modes of 8255 a) I.O Mode i. Mode 0-Simple Input/Output. ii. Mode 1-Strobed Input/Output (Handshake mode) iii. Mode 2-Strobed bidirectional mode

Q. For the mechanical spring-mass-friction system shown in Figure, the differential equation relating the force F(t) and the velocity u(t) is given by  where M is themass,D

Question: Figure shows the basic circuit of the BJT Common Emitter Amplifier. (a) What is the function of RB, RC, Ci, Co and CE ? (b) (i) Sketch the d.c. equivalent circu

List the different types of flags affected by the arithmetic and logic operations. Carry flag, Auxiliary carry flag , Parity flag, Sign flag, Zero flag

Q. Explain the use of CRO for frequency measurement.   Measurement of frequency: The frequency of the periodic signals is easily measured with a CRO. The frequency of a si

Revision  of Basics Although  it is  assumed in this book  that the  reader has  enough  knowledge of  various number systems ( binary, octal and hexadecimal and their relation

Discuss need of Pipelining. The simplest method for improving performance by hardware parallelism is pipelining. Pipelining has breaking up the operations to be performed in s