--- title: "Encode 10010110001 with NRZ-L, NRZ-I, diff. Manchester" subject: "Data Communication" chapter: 5 key: "semester_5/data_communication:line-coding-10010110001" source: https://www.bctengineer.com/q/semester_5/data_communication/line-coding-10010110001 site: BCT Engineering --- # Encode 10010110001 with NRZ-L, NRZ-I, diff. Manchester Data Communication · Chapter 5: Data Encoding and Modulation - Asked in: 2075 Asoj, 2×3 marks - Video: [Polar Mechanism ( NRZ-L || NRZ-I || RZ || Manchester || Differential Manchester )](https://www.youtube.com/watch?v=2YmOb79ioAA) — Ahmed Magdy - Answer checked by Claude Sonnet 5.5 on 2026-10-14 - Page: https://www.bctengineer.com/q/semester_5/data_communication/line-coding-10010110001 - Whole chapter: https://www.bctengineer.com/md/semester_5/data_communication/chapter-5 ## Question Encode the bit stream 10010110001 using the following encoding schemes: (i) Polar NRZ-L (ii) Polar NRZ-I (iii) Differential Manchester ## Short answer NRZ-L: 1=+V, 0=-V; waveform directly represents bits. NRZ-I: toggles at start of each 1, stays same for 0 (initial low). Differential Manchester: always mid-bit transition; a 0 adds an extra transition at the start, a 1 has none. ## Answer Bit stream: 1 0 0 1 0 1 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. #### Polar NRZ-L ```text 1 0 0 1 0 1 1 0 0 0 1 +V ----| |---| |-------| |--- 0 | | | | | | -V |-------| |---| |-----------| ``` #### Polar NRZ-I ```text 1 0 0 1 0 1 1 0 0 0 1 +V ------------| |---| |--- 0 | | | | -V |-------| |---------------| ``` #### Differential Manchester ```text 1 0 0 1 0 1 1 0 0 0 1 +V |-| |-| |---| |-| |---| |-| |-| |-| |- 0 | | | | | | | | | | | | | | | | | -V --| |-| |-| |-| |---| |-| |-| |-| |---| ``` #### Rules used - **NRZ-L**: level = bit value (1 = +V, 0 = -V). - **NRZ-I**: the level changes at the start of every 1; it stays the same for a 0. - **Differential Manchester**: there is always a transition in the middle of the bit (clock); a 0 has an extra transition at the start of the bit and a 1 has none. ## Check yourself The answer's key points as multiple-choice questions, with the correct option and why. 1. NRZ-L: level equals: A. Toggle on 1 B. Bit value (1 = +V, 0 = -V) C. Mid-bit transition D. Alternating Answer: B. By convention. (Key point: NRZ-L) 2. NRZ-I changes level: A. At every 0 B. Mid-bit C. At the start of every 1 D. Never Answer: C. A 0 keeps level. (Key point: NRZ-I) 3. Differential Manchester has: A. No mid-bit transition B. Start transition for 1 C. Only on 1s D. Always a mid-bit transition; extra at start for 0 Answer: D. Clock. (Key point: Diff Manchester) 4. With low initial level, the first 1 gives: A. +V B. -V C. 0 V D. No change Answer: A. Toggle. (Key point: NRZ-I result) ## 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× - [Polar, unipolar, bipolar, Manchester; encode 101000111011](https://www.bctengineer.com/question.md?key=semester_5%2Fdata_communication%3Aline-coding-101000111011) — Data Communication, chapter 5 - [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 1001101110 with unipolar, polar, bipolar codes](https://www.bctengineer.com/question.md?key=semester_5%2Fdata_communication%3Aline-coding-1001101110) — Data Communication, chapter 5, asked 3× - [Encode 10110001110 with unipolar, polar, bipolar codes](https://www.bctengineer.com/question.md?key=semester_5%2Fdata_communication%3Aline-coding-10110001110-68c) — Data Communication, chapter 5, asked 3× - [Line coding: properties; encode 01001100011](https://www.bctengineer.com/question.md?key=semester_5%2Fdata_communication%3Aline-coding-01001100011) — 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×