1A

Question 1

Frequency =

Answer 1

cycles per second

Question 2

Bandwidth =

Answer 2

bits per second

Question 3

This time is based off the apparent location of the sun.

Answer 3

Apparent Solar Time

Question 4

Instruments, such as ___, help us use the location of the sun to give us the time of day.

Answer 4

sundials

Question 5

The least accurate timing measure, it is still used in some parts of the world today.

Answer 5

Apparent Solar Time

Question 6

Quartz Oscillators are also known as?

Answer 6

Crystal Oscillators

Question 7

These function by resonating a tuned voltage through a crystal and the result is a resonated frequency that we use for timing.

Answer 7

Quartz Oscillators

Question 8

Quartz oscillators function by resonating a tuned voltage through
a crystal and the result is a resonated frequency that we use for timing. This process is called the…?

Answer 8

piezoelectric effect

Question 9

While quartz oscillators are widely used in everything from wrist watches to laboratory equipment, their accuracy and stability are affected by ___ and ___, causing them to drift in frequency.

Answer 9

temperature
age

Question 10

Quartz oscillators are the least ___ of the oscillators.

Answer 10

accurate

Question 11

Quartz oscillators require ___ ___ to stay precise.

Answer 11

periodic calibration

Question 12

These oscillators take advantage of atom molecules.

Answer 12

Atomic oscillators

Question 13

At certain frequencies, atoms release ___ that can be utilized as timing.

Answer 13

radiation

Question 14

Also, atoms are not subject to the aging process or impacted by temperature, so they consistently stay at a ___ ___.

Answer 14

stable rate

Question 15

Other kinds of atomic clocks have also been developed for various applications; those based on ___ offer exceptional stability, for example.

Answer 15

hydrogen

Question 16

Today, two of the most common types of atomic oscillators are
the…?

Answer 16

cesium beam oscillator and the rubidium gas cell oscillator

Question 17

A cesium beam oscillator’s atomic resonance is

Answer 17

9,192,631,770 Hertz (Hz) (9.192 GHz)

Question 18

The beam is created by passing ___ metal through high heat creating the beam. The beam is put through a cavity, charging the atoms, and producing a current.

Answer 18

Cesium

Question 19

Cesium beam oscillators are highly stable and drift only ___ nanoseconds (ns) in 24 hours.

Answer 19

200

Question 20

Due to their high stability, they are considered primary frequency standards.

Answer 20

Cesium Standard

Question 21

Rubidium oscillators use a “gas cell” containing rubidium gas whose atomic resonance is at

Answer 21

6,834,682,608 Hz (6.384 GHz)

Question 22

Rubidium oscillators drift approximately ___ microsecond (μs)
every 24 hours, which means it must be calibrated periodically.

Answer 22

1

Question 23

The secondary frequency standard.

Answer 23

Rubidium Standard

Question 24

Rubidium has advantages over cesium, such as…?

Answer 24

more compact
lower in cost
more power efficient

Question 25

In SATCOM ___ can be used to provide a timing standard to our equipment.

Answer 25

GPS

Question 26

GPS timing is accomplished generally by deploying a ___ ___ whose job is to collect timing data from satellites.

Answer 26

passive antenna

Question 27

When being created, the GPS constellation was designed to provide ___-___ visibility from anywhere in the world. However, the more satellites that the antenna can pick-up the more accurate the timing will be.

Answer 27

four-satellite

Question 28

The four standards for synchronization are:

Answer 28

plesiochronous, mutual, master clock, and master-slave.

Question 29

This synchronization technique does not require synchronization between nodes. Instead, it provides a highly stable clock at each station, eliminating the need distribute time across the network.

Answer 29

Plesiochronous

Question 30

This synchronization technique requires all network nodes have their own clocks for timing. However, the clocks are not required to be as precise. Instead, average clock data is collected from all the nodes so that all stations can operate off the same clock frequency. Network timing continues to adjust as network nodes connect and disconnect from the network. While ____ timing requires all nodes to be connected, it does not pin a single point of failure on an unreliable node.

Answer 30

Mutual

Question 31

This technique requires one node to be the master station. The master stating distributes timing to all other stations. A small network can benefit from this method, but it does not scale well. In a larger network, too many nodes can create issues with too many connections. There is also a single point of failure in the master station. If the master station fails, the entire network goes down.

Answer 31

Master Clock

Question 32

This is the most reliable synchronization technique. This method functions similar to a domino effect; one node is still required to be the master station, but after the clock signal has been distributed to the first set of subordinate nodes, it is then passed to the next level by those nodes. This method is the most robust due to the redundancy of higher subordinate nodes providing timing, and because all nodes are expected to have back-up clocks.

Answer 32

Master-Slave