M&MA

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Exploring the world of multiplexing and multiple access: How it improves communication efficiency

Communication is an essential part of our daily lives, and we rely on it for almost everything we do . From sending a text message to streaming a video , we use different communication systems to connect with the world . However, these systems are often limited by the amount of available bandwidth, which can cause congestion and delays. This is where multiplexing and multiple access come in . Multiplexing and multiple access are two techniques that are used to improve the efficiency and capacity of communication systems. In this post , we will explore what multiplexing and multiple access are, the different types of multiplexing and multiple access techniques, and how they are used in different communication systems. Multiplexing is a technique that allows multiple signals to share the same communication channel. It enables the simultaneous transmission of multiple signals over a single channel, which increases the capacity and efficiency of the c

Mobile Terminated Call in GSM

Mobile Terminated Call • The calling party dials the MSISDN for the mobile subscriber. • The PSTN identifies the network (PLMN) that the dialed MSISDN belongs to and will locate a GMSC for that network. • The PSTN sends an Initial Address message to the GMSC. •T he GMSC forwards the MSISDN to the HLR and requests routing information for it. • The HLR looks up the MSISDN and determines the IMSI and the SS7 address for the MSC/VLR that is servicing the MS. •T he HLR then contacts the servicing MSC/VLR and asks it to assign a Mobile Station Routing Number (MSRN) to the call. (a MSRN is assigned to the call not to the MS itself. ) • The MSC/VLR allocates the MSRN and forwards it to the HLR.

Call Setup GSM Flow

GSM Call Flow (GSM Originating Call) Call Setup GSM Flow Call Setup GSM Flow: • The MSC sends an Initial Address Message (IAM) to the GMSC. The IAM contains the MSISDN of the called party as the MS dialed it. • The MSC will also send a Call Proceeding (CALL_PROC) message down to the BSS and this is when the BSS would assign a TCH to the MS, as described earlier • Based on the dialed number, the GMSC decides where to route the IAM within the PSTN. • The PSTN will continue to route the IAM until it reaches the correct Switching Center and the call routing is complete. The PSTN will then establish the call circuit and send an Address Complete Message (ACM) back to the GMSC. • The GMSC then forwards the ACM back to the responsible MSC indicating that the call circuit has been established. Call Establishment • Once the MSC receives the ACM, it sends an ALERT message

What is Ray Model?

Introduction Ray Model 1. Optical fiber is basically a solid glass rod. The diameter of rod is so small that it looks like a fiber. 2. Optical fiber is a dielectric waveguide. The light travels like an electromagnetic wave inside the waveguide. The dielectric waveguide is different from a metallic waveguide which is used at microwave and millimeter wave frequencies. 3. In a metallic waveguide, there is a complete shielding of electromagnetic radiation but in an optical fiber the electromagnetic radiation is not just confined inside the fiber but also extends outside the fiber. 4. The light gets guided inside the structure, through the basic phenomenon of total internal reflection . 5. The optical fiber consists of two concentric cylinders; the inside solid cylinder is called the core and the surrounding 6. For the light to propagate inside the fiber through total internal reflections at core-cladding interface, the refractive index of the core must be greater tha

BROADBAND COMMUNICATION IMPORTANT QUESTIONS

BROADBAND COMMUNICATION QUESTION BANK 1. (a) What are the advantages of optical fiber cables over the co-axial cables? (06) (b) Calculate NA, Acceptance angle and Angle of fiber with core and cladding refractive index values as n 1 =1.5 and n 2 =1.45 respectively. (06) (c) Explain the “mode theory” of optical fiber. (06) 2. (a) What is meant by acceptance angle and acceptance cone for optical fiber? Show and explain it’s relationship to numerical aperture and refractive indices of core & cladding. (06) (b) If a MMSI fiber of core radius 25 micrometer operating at 1300nm, has core and cladding refractive index as 1.5 & 1.38 respectively; Calculate Numerical aperture, Normalized frequency, Solid acceptance angle and number of modes ent

WIRELESS NETWORKS IMPORTANT QUESTIONS

WIRELESS NETWORKS QUESTION BANK QUESTION BANK FOR WIRELESS NETWORKS : Q.1.What are draw back of 2G Services ? What are its silent features of 3G services that overcome the drawbacks of 2G services? Q.2.Discuss the features of IMT2000 that have been adopted in UMTS/3G services. Q.3.Explain the basic concept of WCDMA ?Which is a air interface of UMTS. Q.4.Give the specification of WCDMA air interface .Also explain how the information /message is coded and scrambled in WCDMA Q.5.Explain in brief the physical channels in WCDMA and the function performed by them Q.6.Explain the transport channel in CDMA that are mapped on the physical channel. Q.7.Draw the architecture of 3GPP RELEASE 4 distributed network architecture. Q.8. .Draw the architecture of 3GPP RELEASE 5 All IP multimedia network architecture. Q.9.What is ALL IP network ? Explain its architecture ? Explain its Advantages? Q.10.What is core network ?Explain its architecture ? Q.13.Write a s