344320
Ekco , who manufactured the R1155 and T1154 at its Aylesbury shadow factory , carried out extensive development work on both units before putting them into production , significantly improving on the original Marconi design .
 Marconi
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Marconi