The following pages list UK UHF DTT transmitters. These are arranged by region and then grouped into main stations with the relays in alphabetical

Transcription

1 The following pages list UK UHF DTT transmitters. These are arranged by region and then grouped into main stations with the relays in alphabetical order. The list includes all main sites (in bold), relays that carry the commercial multiplexes and other public service multiplexes ( Freeview Lite ) of ERP 50 W or more. The list includes the planned changes for the channel 61:62 clearance. High-definition services are included on mux BBC B. 91

2 92

3 93

4 94

5 95

6 96

7 Key to columns Ant: Indicates the optimum aerial group and the signal polarisation. Note this is based on after channel 61:62 and takes into account the aerial group amendments. (See page 98). High-definition services are included on mux BBC B. 97

8 Band A B C/D E K W/B T Pre LTE:800 Channels Pre LTE:800 Frequency (MHz) Post LTE:800 Channels Post LTE:800 Frequency (MHz) Mhz Mhz E21-E37 E39-E60 98

9 Duplex Gap Guard Band PMSE 64-QAM 45 dbµv 65 dbµv 23 db 7.5 Mhz 256-QAM 45 dbµv 65 dbµv 26 db 7.9 MHz Recommendations according to DTG 'R-Book 5' & CAI Codes of Practise Cellular Mobile Frequencies Band 2G (GSM) 3G (UMTS) 4G (LTE) Base TX Mobile TX Base TX Mobile TX Base TX Mobile TX LTE GSM GSM UMTS TDD LTE All frequencies are in MHz. Some 2G spectrum is now in use for 3G and 4G services. TDD = Time-division duplex. Long Term Evolution (LTE)/4G Proximity to DTT DTT LTE Base Station Downlink LTE Consumer Unit Uplink 8MHz 8MHz 8MHz 8MHz 8MHz 8MHz 8MHz 8MHz 8MHz 8MHz 10MHz 10MHz 10MHz 10MHz 10MHz 10MHz 10MHz ch ch ch ch ch ch ch ch ch ch Group A Group T PMSE - programme making and special events block A 1MHz block B block C block A 41 Mhz Duplex Spacing block B block C 99

10 Interference from LTE signals on UHF frequencies will be a problem in many installations, both existing and new. Here are some techniques to mitigate the effects of LTE. Problem The main issue will be with the proximity and the levels of power of the LTE transmissions to the existing DTT network. Interference and overload to DTT reception from LTE will be a problem in all areas of the installation. The downlink transmissions from the transmitters will cause problems with interference at the aerial and signal amplification and splitting but there may also be problems from the uplink from LTE consumer mobile devices operating near TVs or other equipment with poorly screened installations and wide band amplifiers. It is important that the correct choices are made when selecting products for installations to make sure they are suitably protected or designed to mitigate the effects of LTE. How to mitigate the problems Aerials Ensure the correct aerial is selected. Ideally only use CAI benchmarked aerials in the correct groups T and A or select the correct group for the transmitter. (See update transmitter list on page 91). LTE is vertically polarised. Where possible choose a horizontal transmission. This will give at least 16 db of rejection to the LTE signal. Consider the position of the aerial. Can it be re-sited to use the local surroundings as screening? (see fig 1). Can a different transmitter less susceptible to LTE be used? LTE interference can be reduced if TV reception is currently from a local vertical DTT transmitter, considering the power increase post DSO, now a distant horizontal DTT can be used instead (see fig 2). Similarly, if possible, change the aerial group from a higher frequency band to a lower frequency e.g. group CD to B or group B to A. (see fig 3). 100

11 Mitigating 4G/LTE (Long Term Evolution) fig 1 fig 2 fig 3 Signal Distribution (Passive and Active) Gain is only needed for channels Gain above this will only amplify the LTE interference. Integral filtering of the LTE signal is good practice and can help to reduce the overall problem. Correctly designed filter which is integrated into the products can provide LTE protection. Only use products that conform to the EMC standard EN Filters High filter rejection of the LTE bands will cure the majority of interference problems from both LTE transmitters and mobile user equipment. Stop band filters or Overlap Blocking filter can be used as appropriate to attenuate unwanted signal. See page 54 for details on filters Filters can also be incorporated into other equipment such as amplifiers to mitigate the problem. See pages for details. Cables, outlet plates and fly leads All these items can be susceptible to LTE if not correctly shielded Fit only high quality cables. The use of CAI benchmarked cable is recommended. Ensure any flyleads conform to EN :2009 for IEC leads or EN :2009 for F type. See page 84 for details. Only fit outlet plates that conform to the EMC standard EN See pages for details. See for updates

12 at800 is a trademark of Digital Mobile Spectrum Limited (DMSL). They are funded by and represent the UK mobile operators who will be launching 4G mobile services at 800 MHz, EE, Telefónica UK (O2), Three and Vodafone. The role is to make sure that television reception still available when 4G mobile services at 800 MHz are launched. Web: 102

13 Creating an account The current default user name ( address) and password have been transferred from the old site. However, if there is a problem logging in please call the sales department or reply to this to have your account created. We'll you your username and password and you'll immediately be able to log into the site. You can then use the Login link top right of each screen to log in. Viewing your account details Once logged in click on Your Account at the top of the screen. From here you can perform a number of functions: View your web order history, with one-click reordering of complete orders. View your company and personal information and change your password. View products that you mark as favourites, making it easy to reorder them. Create and save Carts for regular ordering. View any alerts we've sent you. Fast reordering of previously purchased individual products. Viewing ALL current pending orders. (Styled per OLD Website view) Listing a printable standard order form of item bought to use a re-stocking list. (Styled per OLD Website view) Finding products The new site gives you a number of ways to find products: Dropdown menu or side bar: Both of these expand to show all product categories Previously viewed products this shows the last three products you viewed, with one click taking you through to the product page Featured products, listed on the home page Product search, top right of each page. This powerful search gives you live search results as you type either keywords or product numbers New products are listed at the bottom of each page. Placing orders ENSURE THAT YOU ARE LOGGED IN FIRST! Once logged in you will see your custom pricing across the website. To place an order on the site browse to the product or any catalogue page displaying the red Add to Cart button. Once added to the cart you can still amend the quantities and continue to browse the site. Your cart will be remembered, even when you close down the browser. At the top right of the screen you will see the number of products and cart total. Clicking this takes you to the cart, where you can review your items, select delivery options and place your order. Compare products You can compare several products within any given category. Simply browse to a category and check the Compare box. Click Compare in the bottom right of the main window and you'll see your products side by side with any features that you need to compare. Finding technical information We've worked hard to enhance all of the information on our products. At the bottom of each product page you'll find tabs detailing specific features, any downloads (manuals etc) and related products. You can even ask a question about each product, with the answers visible to other customers. Furthermore we've created various technical documents, which are available from the Technical dropdown menu at the top of the page. That covers all of the main features of the site, but if you'd like information on performing other regular functions please let us know and we'll create more how to guides for you or give guidance over the phone where necessary. Thanks for your custom, and we hope you enjoy the new site! Contact Details: sales@blake-uk.com Tel: + 44 (0) / Tel: + 44 (0) Website: Latest news: LTE FAQ: Twitter:@blakesaerials

14 Protection from LTE is a trade mark of ETSI Aerials Brackets & Installation Equipment AV TV Wall Mounts Coaxial Connectors & Adaptors PROception RF Signal Distribution PROception HDMI Signal Distribution LTE Filtering Products UK R&D