Responses to clarification questions on ISED’s 600 MHz — Proposed TV Transition Objectives and Methodology

Innovation, Science and Economic Development Canada (ISED), in collaboration with the United States, is repurposing the 600 MHz band to include commercial mobile use by repacking over‑the‑air (OTA) TV broadcasting stations more tightly in lower frequencies. As part of this initiative, ISED will develop a Canada‑U.S. transition plan and schedule for broadcast stations. ISED published its transition proposals in its 600 MHz — Proposed TV Transition Objectives and Methodology on October 31, 2016.

The following are responses to clarification questions received regarding the 600 MHz transition. For ease of reference, the transition clarification questions and responses have been grouped under the following themes, noting that ISED has not responded to questions regarding broadcaster compensation:

Note: Minor edits were made to the original questions so that they comply with accessibility and other standards including, but not limited to, punctuation, grammar and readability.

ISED's 600 MHz — Proposed TV Transition Objectives and Methodology: overview

Q1. Slide 4 refers to the draft certificate application process. Will stakeholders have an opportunity to review and comment on the proposed application process? When will a draft be ready?

A1. ISED is reviewing the current certificate application process in an effort to streamline the process during the transition.

Q2. Slide 4 refers to the draft post‑transition rules and framework. What changes are being considered to the current digital television (DTV) rules and framework and when will a draft be available for stakeholders to review and comment?

A2. While ISED does not currently anticipate significant changes to the current DTV rules and framework as a result of the 600 MHz repacking, some technical parameters will be updated to reflect the repurposing results, including the frequency range for the TV broadcasting service.

Q3. Slide 5 refers to timelines. How much time is expected from the time the U.S. incentive auction closes to the publication of the following documents by ISED:
  1. joint allotment plan
  2. joint transition plan
  3. daisy chains
  4. TV transition Statement of Interest (SOI)
  5. post‑transition SOI

A3. ISED intends to release the joint allotment plan and the joint transition plan, and identify daisy chains / station dependencies shortly after the U.S. incentive auction concludes. It is important to note that this will also mark the beginning of the transition. The two SOI documents are expected to be released within 30 days of the allotment plan release.

Q4. Slide 7 refers to prioritizing stations. Is the priority for U.S. stations the same as the proposed priority for Canadian stations? Will this impede the ability for Canadian broadcasters to change channels?

A4. Though similar, Canada has proposed slightly different transition priorities and objectives from those proposed by the U.S. (e.g. Canada's priority is to allow additional time for Canadian stations to transition, whereas the U.S. priority is to clear stations in the 600 MHz band). The joint Canada‑U.S. transition plan and schedule will be developed to account for and balance the transition needs and priorities of both countries. Canadian and U.S. stations that have dependencies will be treated equally.

Q4a) Is "dependency" defined as a station that is impeded from moving by another station, or a station which is impeding another station, or both? During the transition, will Canadian stations be subject to interference from U.S. mobile operations in the 600 MHz band?

A4a) Dependency refers to a given station (Station B) that is unable to transition until another station (Station A) has moved to its final channel because the current channel of Station A interferes with the future channel of Station B. These are also referred to as "linked stations".

Although in ISED's Decision on Repurposing the 600 MHz Band, Canadian TV stations in the 600 MHz band will receive one‑year and two‑year displacement notifications prior to mobile deployment, the joint Canada‑U.S. transition plan and schedule has not yet been finalized. Part of Canada‑U.S. negotiations on the transition framework involves the relationship between Canadian TV stations and U.S. mobile service deployment. (See also questions 6 and 15)

Q4b) What are the proposed criteria in determining whether or not a temporary channel is justified?

A4b) The use of temporary channels during the transition would require an additional channel move and may lead to increased temporary interference. ISED proposes not assigning temporary channels to TV stations during the transition process. However, it will consider broadcasters' requests to use a temporary channel during the transition on an exceptional case‑by‑case basis. Among the factors considered for such requests are the impacts on the operation of other stations and their ability to transition on schedule.

Q4c) Will the application process be the same for all stations, or will they differ for stations that propose operating parameters other than those specified in the joint allotment plan?

A4c) As with the DTV transition of 2011, the application process may differ for stations that propose operating parameters which conform to the new DTV allotment plan and those proposing parameters that differ from the plan. ISED is reviewing the certificate application process in an effort to streamline the process during the transition.

Q4d) What variance in operating parameters will be deemed equivalent to the joint allotment plan by the CRTC and by ISED?

A4d) In Broadcasting procedures and rules BPR-10, Application Procedures and Rules for Digital Television (DTV) Undertakings, ISED deems a station's operating parameters equivalent as follows:

  • the application is for the same channel as listed in the allotment plan, and
  • the noise‑limited bounding contour does not exceed the contour as calculated using the relevant parameters and limitations listed in the plan.
Q5. Slide 8 refers to dependencies and daisy chains. What is the maximum time considered for temporary interference?

A5.  The potential for temporary interference occurs when there is a mix of stations operating on their pre‑repacking channel and post‑repacking channel within geographical proximity. In the worst case scenario, temporary interference may be present from the on‑air testing period of phase 1 until the completion of the transition, although this is highly unlikely. Furthermore, in ISED's proposal:

  • temporary interference is limited to 2% pairwise (i.e. station‑to‑station) during the transition; and
  • potential interference exceeding 2% pairwise will be confined to the on‑air testing periods and mitigated by coordination among broadcasters involved in a linked‑station set (i.e. stations that could potentially interfere with others transitioning in the same phase).
Q6. Slide 10 refers to the number of phases. Will the Canadian time extension beyond 39 months include stations in the 600 MHz Band which may cause temporary interference to new U.S. mobile operations?

A6. The joint Canada‑U.S. transition plan and schedule has not yet been finalized. While ISED proposes to extend the transition in Canada beyond 39 months with additional phases, the relationship between TV stations and mobile deployment is part of transition framework negotiations.

Q7 Slide 11 refers to the assignment of stations to phases.

Q7a) Can ISED elaborate on what is meant by stations with "Canadian only dependencies" which would not cause interference to other stations?


  • Stations with "Canadian‑only dependencies" include stations that have dependencies only with other Canadian stations.
  • Stations with "no dependencies" include stations that do not have any dependencies with any other Canadian or American station.

Q7b) Will stations with "Canadian‑only dependencies" be treated differently than those with "no dependencies"?

A7b) ISED has proposed to schedule stations within both of these groups in later phases to allow additional time for their transition. Stations with "no dependencies" were proposed to be scheduled later than those stations "with dependencies" as they have less of an effect on the overall transition schedule and do not impact the ability of other stations to change channel and/or convert to digital. The actual station dependencies for individual stations will not be determined until the new channel assignments are known after the conclusion of the U.S. incentive auction.

Q7c) How will the "regions" be selected or defined?

A7c) The intent is to group stations based on the main market they serve, despite the physical location of their transmitter. For example, stations physically located in Gatineau (QC) or Ottawa (ON) whose main market is the National Capital Region would be part of the same region.

Q8. Slide 14 refers to temporary transition rules. How will ISED define 2% additional interference? By population? By geographic area?

A8. Similar to the calculation of additional interference used in the repacking process, the temporary 2% additional interference is calculated with respect to the baseline interference‑free population of the current station. The baseline interference‑free population is defined as the population within the noise‑limited bounding contour (NLBC) predicted to receive service.

Q9. Slide 16 refers to station assignment objectives.

Q9a)  How will ISED ensure that the maximum number of Canadian stations will retain their existing channel assignments in the new joint allotment plan?

A9a) Channel assignments are part of the repacking process. The repacking system will use optimization techniques to determine a final television channel assignment plan. In addition to satisfying the constraints outlined in the SOI, stations will be repacked based on maximizing the number of stations assigned to their current channels instead of being assigned to new channels. The same optimization algorithm will be applied to all Canadian and U.S. stations to ensure that stations in both countries are treated equally.

Q9b) Will moving U.S. stations in the mobile band first increase the extent or duration of temporary interference to Canadian stations?

A9b) The impacts will not be known until the close of the U.S. auction. However, depending on the configuration of the new DTV allotment plan, moving U.S. stations in the mobile band first may increase the extent and duration of temporary interference to some Canadian stations. On the other hand, scheduling Canadian stations in later phases may also increase the extent and duration of temporary interference to some U.S. stations. The transition plan and schedule will be developed to account for and balance the transition needs and priorities of both countries.

Q10. Slide 18 refers to the length of phases. Which milestone is indicated by month "0"? Does it refer to a station for which applications have been approved by ISED and the Commission?

A10. "Month 0" refers to the publication of the new DTV allotment plan.

Q11. How does ISED propose to engage tower rigging companies in discussions regarding transition scenarios and scheduling?

A11. ISED recognizes the broad range of industry personnel necessary to successfully implement the transition plan, including broadcasters, broadcast consultants and engineers, radiofrequency and structural engineers, equipment manufacturers and suppliers, and other support companies.

ISED engaged broadcasting equipment manufacturers, tower rigging companies, as well as structural engineering consultants to better understand their capacity, capabilities and plans for the transition. This information has been used to develop proposed objectives and methodology for the transition plan.

Q12. Slide 21 refers to construction. Can ISED confirm that there are 22 tower crews in Canada that are experienced in high power broadcast antennas on tall towers?

A12. In July and August, ISED engaged several Canadian firms that provide tower-related services. Based on these discussions, we understand that there are at least 22 tower crews in Canada. While all tower crews may not be readily available to work on high power, tall broadcast towers, the majority of broadcast structures in Canada are less than 100 metres high and are low power. We also understand that the skillset could be transferrable over time with experience gained during the transition.

Furthermore, tower crews from the U.S. and other countries may also be interested in working with Canadian broadcasters during the transition, which would further supplement the number of tower crews available to work on the transition in Canada.

Q13. Slide 22 refers to other considerations. What is the basis for the additional time requirements of only 5% and 10% for multiple stations on a shared site?

A13. For stations that share a tower, there may be benefits in using the same tower crew already on site. It can help to efficiently streamline tower tasks associated with multi‑tenant sites, while avoiding multiple crew‑mobilization and demobilization and multiple rigging and de‑rigging of the tower. Through discussions with tower rigging companies, ISED was advised that significant time could be saved in cases where multiple stations on the same tower are modified at the same time.

General transition rules, scheduling and impact

Q14. What opportunity is there for stations to continue operating in the 600 MHz band until after this spectrum is auctioned in Canada? What impact will there be on timing or scheduling to move Canadian stations as a result of U.S. mobile operators utilizing the 600 MHz band?

A14. As per ISED's Decision on Repurposing the 600 MHz Band, regular power TV stations operating in the to‑be‑repurposed 600 MHz band will be permitted to continue using their current channels and modes of operation until the spectrum is required for the deployment of mobile broadband services. Notification will be issued when displacement is required as a result of mobile deployment. Stations located in urban areas will be granted a one‑year minimum notification period and those located in all other areas, a minimum of two years. This one‑year or two‑year displacement notification may overlap with the scheduled transition date, depending on timing (i.e. schedule and mobile service deployment).

The joint Canada‑U.S. transition plan and schedule has not yet been finalized. Part of Canada‑U.S. negotiations on the transition framework involves the relationship between Canadian TV stations and U.S. mobile service deployment.

Q15. What resources will ISED contribute towards schedule coordination?

A15. ISED, in collaboration with the FCC, will develop a joint transition plan and schedule, with defined dates for stations to transition to new channels and/or convert to digital. Furthermore, ISED has dedicated resources to help ensure that the administrative requirements associated with the transition do not impede its implementation.

Q16. If the transition plan ultimately requires some degree of temporary interference, does it imply that stations that are not changing channel would not incur such interference?

A16. Due to the complexity of the transition process, temporary increases in permissible interference levels are required to address sequential dependencies between stations in the same or adjacent markets. The potential for temporary interference occurs when there is a mix of stations operating on their original channel and post‑repacked channel. A temporary additional increase in pairwise interference between stations of up to 2% is proposed during the transition. This would also apply to stations that are not changing channel.

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