---
title: "AMI and Manchester for 011010001"
subject: "Data Communication"
chapter: 5
key: "semester_5/data_communication:line-coding-011010001"
source: https://www.bctengineer.com/q/semester_5/data_communication/line-coding-011010001
site: BCT Engineering
---

# AMI and Manchester for 011010001

Data Communication · Chapter 5: Data Encoding and Modulation

- Asked in: 2071 Chaitra, 3+3 marks
- Video: [LINE CODING IN DIGITAL COMMUNICATION | Hindi | Unipolar, Polar and Bipolar RZ, NRZ waveforms](https://www.youtube.com/watch?v=sFQpBhbNQgQ) — Electronics Subjectified
- Answer checked by Claude Sonnet 5.5 on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_5/data_communication/line-coding-011010001
- Whole chapter: https://www.bctengineer.com/md/semester_5/data_communication/chapter-5

## Question

Draw AMI and Manchester encoding for the sequence [0 1 1 0 1 0 0 0 1].

## Short answer

AMI: 1s alternate +V and -V starting +V, 0=0V; pattern 0+-0+000-. Manchester: 1=low-to-high mid-bit transition, 0=high-to-low.

## Answer

Bit stream: 0 1 1 0 1 0 0 0 1

**Conventions used** (state these in the exam, as books differ): level before the first bit is low (-V); NRZ-L/RZ: 1 = +V, 0 = -V (unipolar: 0 = 0 V); NRZ-I: a 1 toggles the level at the start of the bit, a 0 keeps it; RZ: the pulse returns to zero in the middle of the bit; Manchester: 1 = low-to-high and 0 = high-to-low transition at mid-bit; differential Manchester: always a mid-bit transition, an extra transition at the start of the bit for a 0 and none for a 1; AMI: 0 = 0 V, 1s alternate +V and -V starting with +V.

#### AMI
```text
      0   1   1   0   1   0   0   0   1  
+V       |---|       |---|               
 0   ----|   |   |---|   |-----------|   
-V           |---|                   |---
```

#### Manchester
```text
      0   1   1   0   1   0   0   0   1  
+V   --|   |-| |---|   |---| |-| |-|   |-
 0     |   | | |   |   |   | | | | |   | 
-V     |---| |-|   |---|   |-| |-| |---|
```

AMI pulses: 0 + - 0 + 0 0 0 - (the four 1s alternate in polarity; 0 = 0 V). Manchester has a transition in the middle of every bit (1 = low-to-high, 0 = high-to-low).

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. For 0 1 1 0 1 0 0 0 1, what is the AMI pulse sequence?
   A. 0 + + 0 + 0 0 0 +
   B. 0 + - 0 + 0 0 0 -
   C. 0 - + 0 - 0 0 0 +
   D. 0 + - 0 - 0 0 0 +
   Answer: B. The four 1s alternate + - + -, with 0 bits at 0 V. (Key point: AMI pulses)

2. In this convention, how is a 0 encoded in Manchester?
   A. Low-to-high at mid-bit
   B. High-to-low at mid-bit
   C. 0 V for the whole bit
   D. No transition
   Answer: B. 0 is a high-to-low mid-bit transition; 1 is low-to-high. (Key point: Manchester 0)

3. What level does AMI use for a 0 bit?
   A. -V
   B. +V
   C. 0 V
   D. Alternating -V and +V
   Answer: C. In AMI zeros are at 0 V and only 1s alternate in polarity. (Key point: AMI zero level)

## Related in Data Communication

- [Encode 1101001 with polar NRZ, AMI, Manchester](https://www.bctengineer.com/question.md?key=semester_5%2Fdata_communication%3Aline-coding-1101001) — Data Communication, chapter 5, asked 3×
- [Encode 10101111000011 with NRZ, RZ, AMI, Manchester](https://www.bctengineer.com/question.md?key=semester_5%2Fdata_communication%3Aline-coding-10101111000011) — Data Communication, chapter 5
- [Encode 10010110001 with NRZ-L, NRZ-I, diff. Manchester](https://www.bctengineer.com/question.md?key=semester_5%2Fdata_communication%3Aline-coding-10010110001) — Data Communication, chapter 5

## Related in other subjects

- [Line coding 1011001010 (polar NRZ, polar RZ, Manchester, AMI)](https://www.bctengineer.com/question.md?key=semester_6%2Fcommunication_systems%3Aline-codes-1011001010) — Communication Systems, chapter 6, asked 8×
- [Line coding 1001001101 (polar NRZ, polar RZ, Manchester, AMI)](https://www.bctengineer.com/question.md?key=semester_6%2Fcommunication_systems%3Aline-codes-1001001101) — Communication Systems, chapter 6, asked 8×
- [Line coding 1001101101 (unipolar NRZ, polar RZ, AMI, Manchester)](https://www.bctengineer.com/question.md?key=semester_6%2Fcommunication_systems%3Aline-codes-1001101101) — Communication Systems, chapter 6, asked 8×
- [Line coding 1101010111 (polar NRZ, polar RZ, Manchester, AMI)](https://www.bctengineer.com/question.md?key=semester_6%2Fcommunication_systems%3Aline-codes-1101010111-polar-ami) — Communication Systems, chapter 6, asked 8×