Author Archives: mrcolville


Being able to add and resolve vectors is one of the key maths skills you need to access most of the G492 paper. All of the maths is GCSE level but you need to be able to use it without thinking.
Here are some resources to support:


With questions:


Cover work

I will be off until Thursday 2nd October. There are some topics that you need to look at and some questions to do (which can all be found on the student shared drive).
There are some links below to support. We will go through the key points when I return.

Please make notes on:
magnification, the difference between analogue and digital signals, how analogue signals can be converted into digital signals, polarisation. Please go through the checklist for chapter 1 in you booklet and produce revision notes for the chapter.

Ch1 160C Satellite images (comprehension questions)
Ch3 10E Making estimates about information (estimation questions)
Ch3 70S Sampling and hearing (short answer questions)
Ch3 130S Polarisation in satellite communication (short answer questions)

This is the cover work for the lessons. You should continue to set yourself homework tasks outside of the lesson time.

You need to know how to calculate magnification for values of U and V and image and object size

Digital and analogue signals
In order to store and transmit informations with a computer it needs to be in a digital format. You need to know what analogue signals are and how to convert them to digital signals.

You need to know what it is and how it can be used in communication.

Image processing

A digital image is made up of pixels which each have a numerical value associated with the pixel colour. When we process an image we change the pixel values.
Median – removes noise
Mean – smooths the image
Edge finding – finds the edge fan object
Spreading pixel values – adjusts contrast

Some background ideas

Bits and bytes

Digital information is stored as a string of 0’s and 1’s. Each number is referred to as a bit. The more bits we have the more different arrangements there are of the 0’s and 1’s.

We need to be able to calculate the number of different arrangements a given number if bits will give us and how many bits will be required to cover a given number of arrangements.
You don’t need to use logarithms for the questions that will be set. Here is some extra support on how they work:

Remember there are 8 bits in a byte and the prefixes are slightly different to normal.