READING TEST 1

In digital passband transmission, the incoming data STREAM is modulated into a carrier with fixed frequency and then transmited over a band-pass channel. Passband digital transmission allows more efficient use of the allocated RF bandwidth, and flexibility in accommodating different baseband signal formats. The word "stream" as used in the first line could be best replaced by the word:

Digital modulation techniques are classified into coherent and noncoherent techniques, depending on whether the receiver is equipped with a phase-recovery circuit or not. The phase-recovery circuit ensures that the local oscillator in the receiver is synchronized to the incoming carrier wave (in both frequency and phase). There are just TWO types of digital modulation techniques.

Closed-loop systems are designed to automatically achieve and maintain the desired output condition by comparing it with the actual condition. It does this by generating an error signal which is the difference between the output and the reference input. In other words, a “closed-loop system” is a fully automatic control system in which its control action being dependent on the output in some way. What it the main characteristic of a "closed-loop system"?

Look at the closed-loop control diagram. Which of th following statments is NOT true?

The primary goal of CISC architecture is to complete a task in as few lines of assembly as possible. This is achieved by building processor hardware that is capable of understanding and executing a series of operations. For this particular task, a CISC processor would come prepared with a specific instruction (we'll call it "MULT"). The phrase "as few lines of assembly as possible" implies that:

RISC processors only use simple instructions that can be executed within one clock cycle. Thus, the "MULT" command described above could be divided into three separate commands: "LOAD," which moves data from the memory bank to a register, "PROD," which finds the product of two operands located within the registers, and "STORE," which moves data from a register to the memory banks. In order to perform the exact series of steps described in the CISC approach, a programmer would need to code four lines of assembly. The number of steps must correspond to the number of code lines.